Journal of Materials Processing Technology最新文献_第5页

Direct preparation of laser-induced doped graphite films on glass surfaces under domain-limiting effect for photonic debonding 在限域效应下在玻璃表面直接制备激光诱导掺杂石墨薄膜用于光子脱粘

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-17 DOI: 10.1016/j.jmatprotec.2026.119214

Wenxue Dai , Fangcheng Wang , Ping He , Huijuan Liu , Chenghao Ma , Qiang Liu , Mingqi Huang , Guoping Zhang , Bingpu Zhou , Rong Sun

Constructing doped carbon-based multifunctional films with stable structures and excellent adhesion on glass substrates represents a core challenge and research focus in contemporary materials processing. Traditional high-temperature fabrication processes often suffer from aging and agglomeration of dopant particles, leading to reduced film structural uniformity and severely limiting their application potential in broad-spectrum light absorption and efficient thermal management. Here, we propose an in situ preparation method for laser-induced doped graphite films (LDGF) based on the domain-limiting effect, enabling the one-step construction of multifunctional release layers on glass surfaces. This approach utilizes the localized transient thermal field and non-equilibrium dynamics induced by ultraviolet lasers to promote the formation of stable interlayer bridging structures between metal ions and heteroatoms within the defective carbon matrix. The photothermal shock resistance of the LDGF film stems from the interfacial adhesion established through local substrate re-deposition and is further enhanced by the mechanical reinforcement imparted by metal ion bridges. Meanwhile, LDGF exhibits outstanding optical absorption performance (200–1200 nm, >91.99 %), coupled with extremely low light transmittance (<0.01 %). Experiments further demonstrate that LDGF reduces the photonic debonding threshold for identical bonding pairs by approximately 41 %, significantly broadening the applicability and operational window of photonic debonding processes. This laser-induced doping graphitization strategy provides an innovative and feasible material preparation pathway for photothermal conversion layers required in wafer-level and panel-level photonic debonding technologies for advanced packaging.

在玻璃基板上构建结构稳定、附着力优异的掺杂碳基多功能薄膜是当代材料加工领域的核心挑战和研究热点。传统的高温制备工艺往往存在掺杂颗粒老化和团聚的问题，导致薄膜结构均匀性降低，严重限制了其在广谱光吸收和高效热管理方面的应用潜力。本文提出了一种基于区域限制效应的激光诱导掺杂石墨薄膜（LDGF）原位制备方法，实现了在玻璃表面一步构建多功能释放层。该方法利用紫外激光诱导的局域瞬态热场和非平衡动力学来促进缺陷碳基体中金属离子和杂原子之间形成稳定的层间桥接结构。LDGF薄膜的抗光热冲击性能源于通过局部衬底再沉积建立的界面附着力，并通过金属离子桥传递的机械增强进一步增强。同时，LDGF具有出色的光吸收性能（200-1200 nm, >91.99 %）和极低的透光率（<0.01 %）。实验进一步表明，LDGF将相同键对的光子脱键阈值降低了约41% %，显著拓宽了光子脱键过程的适用性和操作窗口。这种激光诱导掺杂石墨化策略为先进封装的晶片级和面板级光子脱粘技术所需的光热转换层提供了一种创新和可行的材料制备途径。

{"title":"Direct preparation of laser-induced doped graphite films on glass surfaces under domain-limiting effect for photonic debonding","authors":"Wenxue Dai , Fangcheng Wang , Ping He , Huijuan Liu , Chenghao Ma , Qiang Liu , Mingqi Huang , Guoping Zhang , Bingpu Zhou , Rong Sun","doi":"10.1016/j.jmatprotec.2026.119214","DOIUrl":"10.1016/j.jmatprotec.2026.119214","url":null,"abstract":"<div><div>Constructing doped carbon-based multifunctional films with stable structures and excellent adhesion on glass substrates represents a core challenge and research focus in contemporary materials processing. Traditional high-temperature fabrication processes often suffer from aging and agglomeration of dopant particles, leading to reduced film structural uniformity and severely limiting their application potential in broad-spectrum light absorption and efficient thermal management. Here, we propose an in situ preparation method for laser-induced doped graphite films (LDGF) based on the domain-limiting effect, enabling the one-step construction of multifunctional release layers on glass surfaces. This approach utilizes the localized transient thermal field and non-equilibrium dynamics induced by ultraviolet lasers to promote the formation of stable interlayer bridging structures between metal ions and heteroatoms within the defective carbon matrix. The photothermal shock resistance of the LDGF film stems from the interfacial adhesion established through local substrate re-deposition and is further enhanced by the mechanical reinforcement imparted by metal ion bridges. Meanwhile, LDGF exhibits outstanding optical absorption performance (200–1200 nm, >91.99 %), coupled with extremely low light transmittance (<0.01 %). Experiments further demonstrate that LDGF reduces the photonic debonding threshold for identical bonding pairs by approximately 41 %, significantly broadening the applicability and operational window of photonic debonding processes. This laser-induced doping graphitization strategy provides an innovative and feasible material preparation pathway for photothermal conversion layers required in wafer-level and panel-level photonic debonding technologies for advanced packaging.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119214"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Synchronous multidirectional extrusion based on uniaxial load assembled toggle-arm mechanisms: A case study on 2195 Al-Li alloy 基于单轴载荷组合切换臂机构的同步多向挤压：以2195铝锂合金为例

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-16 DOI: 10.1016/j.jmatprotec.2026.119221

Peng Jia , Xusheng Chang , Xiaoyu Shen , Zhuoxun Yi , Yushi Qi , Gang Chen , Qiang Chen

Synchronous extrusion from independent directions for each port is a potential approach for manufacturing multidirectional structural components (MDSCs). However, its universality and flexibility are limited by the need for specific forming devices, and the accuracy constraints of these devices may lead to folding defects and non-uniform microstructures. To address these challenges, this study proposes a synchronous multidirectional extrusion (SMDE) method based on uniaxial load. The uniaxial load is synchronously decomposed and redirected into multiple independent movements by toggle-arm mechanisms. This method allows excellent flexibility in manufacturing MDSCs since almost arbitrary load direction is available by adjusting the angle and size of the toggle-arm. Moreover, the load synchrony will be easier enabled by the rigidity of toolsets rather than the accuracy of the devices. The feasibility of SMDE was demonstrated by manufacturing an MDSC with square ports and orthogonal ribs using 2195 aluminum-lithium alloy. The investigations in material flow and microstructures at different forming stages revealed non-uniform forming mechanisms influenced by the nonlinear kinematic characteristics and multidirectional discrepancies. Results show that the progressive reduction in horizontal velocity, combined with additional compression, reduces inter-directional variations in height of thin-walled ports, improving the dimensional accuracy. Meanwhile, the active control of nonuniform deformation with additional compression promotes uniform dynamic recrystallization and grain refinement, leading to uniform microstructures and near-isotropic properties across the ports. The average yield strength, ultimate tensile strength, and elongation were tested to be 487.4 MPa, 529.4 MPa and 8.2 %, respectively. Moreover, the strength heterogeneity of the tested ports was calculated to below 1.39 %. This work provides theoretical and experimental guidance for optimizing of multidirectional load paths and actively controlling nonuniform deformation, and offers a novel and efficient method for the precision forming of MDSCs with arbitrary orientations.

从每个端口的独立方向同步挤压是制造多向结构部件（MDSCs）的潜在方法。然而，其通用性和灵活性受到特定成形装置需求的限制，这些装置的精度约束可能导致折叠缺陷和不均匀的微观结构。为了解决这些挑战，本研究提出了一种基于单轴载荷的同步多向挤压（SMDE）方法。通过切换臂机构，将单轴载荷同步分解并重定向为多个独立的运动。这种方法在制造MDSCs方面具有优异的灵活性，因为通过调整切换臂的角度和尺寸，几乎可以实现任意负载方向。此外，负载同步将更容易通过工具集的刚性而不是设备的精度实现。以2195铝锂合金为材料，制备了方孔正交肋MDSC，验证了SMDE的可行性。对不同成形阶段的材料流动和微观组织的研究揭示了受非线性运动特性和多向差异影响的非均匀成形机制。结果表明，水平速度的逐渐减小，加上附加压缩，减小了薄壁孔口高度的方向变化，提高了尺寸精度。同时，主动控制非均匀变形和额外压缩促进了均匀的动态再结晶和晶粒细化，导致了均匀的显微组织和近各向同性的性能。平均屈服强度为487.4 MPa，极限抗拉强度为529.4 MPa，延伸率为8.2 %。此外，计算出测试端口的强度异质性小于1.39 %。该研究为多向加载路径的优化和非均匀变形的主动控制提供了理论和实验指导，为任意取向MDSCs的精密成形提供了一种新颖有效的方法。

{"title":"Synchronous multidirectional extrusion based on uniaxial load assembled toggle-arm mechanisms: A case study on 2195 Al-Li alloy","authors":"Peng Jia , Xusheng Chang , Xiaoyu Shen , Zhuoxun Yi , Yushi Qi , Gang Chen , Qiang Chen","doi":"10.1016/j.jmatprotec.2026.119221","DOIUrl":"10.1016/j.jmatprotec.2026.119221","url":null,"abstract":"<div><div>Synchronous extrusion from independent directions for each port is a potential approach for manufacturing multidirectional structural components (MDSCs). However, its universality and flexibility are limited by the need for specific forming devices, and the accuracy constraints of these devices may lead to folding defects and non-uniform microstructures. To address these challenges, this study proposes a synchronous multidirectional extrusion (SMDE) method based on uniaxial load. The uniaxial load is synchronously decomposed and redirected into multiple independent movements by toggle-arm mechanisms. This method allows excellent flexibility in manufacturing MDSCs since almost arbitrary load direction is available by adjusting the angle and size of the toggle-arm. Moreover, the load synchrony will be easier enabled by the rigidity of toolsets rather than the accuracy of the devices. The feasibility of SMDE was demonstrated by manufacturing an MDSC with square ports and orthogonal ribs using 2195 aluminum-lithium alloy. The investigations in material flow and microstructures at different forming stages revealed non-uniform forming mechanisms influenced by the nonlinear kinematic characteristics and multidirectional discrepancies. Results show that the progressive reduction in horizontal velocity, combined with additional compression, reduces inter-directional variations in height of thin-walled ports, improving the dimensional accuracy. Meanwhile, the active control of nonuniform deformation with additional compression promotes uniform dynamic recrystallization and grain refinement, leading to uniform microstructures and near-isotropic properties across the ports. The average yield strength, ultimate tensile strength, and elongation were tested to be 487.4 MPa, 529.4 MPa and 8.2 %, respectively. Moreover, the strength heterogeneity of the tested ports was calculated to below 1.39 %. This work provides theoretical and experimental guidance for optimizing of multidirectional load paths and actively controlling nonuniform deformation, and offers a novel and efficient method for the precision forming of MDSCs with arbitrary orientations.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119221"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cathode jet and columnar grain suppression in oscillating arc-wire directed energy deposition of titanium alloy 钛合金振荡电弧丝定向能沉积中的阴极喷射和柱状晶粒抑制

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-10 DOI: 10.1016/j.jmatprotec.2026.119215

Kang Sun , Xiao Xiao , Shigeaki Uchida , Pengkang Zhao , Dongsheng Wu , Hisaya Komen , Ning Ma , Keke Zhang , Manabu Tanaka , Huijun Li

As titanium is a thermionic cathode material, strong cathode jet can easily be caused by gas metal arc welding (GMAW)-based directed energy deposition (DED) of titanium alloys. Additionally, during the DED process, coarse columnar grains are prone to form, which severely affects the performance of the deposited titanium components. Therefore, it remains a challenge to fabricate high-performance titanium alloy components using GMAW-based DED. In this work, these obstacles can be overcome using an oscillating arc. Additionally, the influencing mechanisms of the oscillating arc on the cathode jet, droplet transfer, molten pool flow, microstructure, and mechanical properties were investigated. Experimental and simulation results indicated that the metal vapor near the welding wire in conventional GMAW-based DED was primarily composed of Ti ion (Ti Ⅱ) particles, while the cathode jet was mainly composed of Ti atom (Ti Ⅰ) particles. The oscillating arc reduced the molten pool temperature and caused the cathode jet to move away from the droplet. It also shifted the peak intensity of Ti atom particles from the molten pool to the welding wire, while promoting the ionization of a large number of Ti atom particles into Ti ion particles in the cathode jet region. The oscillating arc also promoted convection in the molten pool and altered the flow patterns, which increased the cooling rate and thereby refining the β and α grains. Oscillating cold metal transfer (CMT)-based DED significantly improved the mechanical properties of Ti6Al4V alloy. This work provides new perspectives and guidance for the engineering applications of GMAW-based DED of titanium alloys.

由于钛是一种热离子阴极材料，钛合金的金属气弧焊定向能沉积（DED）容易产生强烈的阴极射流。此外，在DED过程中容易形成粗大的柱状晶粒，严重影响了沉积钛部件的性能。因此，利用gmaw基DED制造高性能钛合金部件仍然是一个挑战。在这项工作中，可以使用振荡电弧克服这些障碍。此外，还研究了振荡电弧对阴极喷射、熔滴传递、熔池流动、微观结构和力学性能的影响机理。实验和模拟结果表明，在传统的gmaw基DED中，焊丝附近的金属蒸气主要由Ti （TiⅡ）颗粒组成，而阴极射流主要由Ti原子（TiⅠ）颗粒组成。振荡电弧降低了熔池温度，使阴极射流远离液滴。它还使钛原子粒子的峰值强度从熔池向焊丝转移，同时促进了大量钛原子粒子在阴极射流区电离成钛离子粒子。振荡电弧还促进了熔池内的对流，改变了流动模式，提高了冷却速度，从而细化了β和α晶粒。振荡冷金属转移（CMT）基DED显著改善了Ti6Al4V合金的力学性能。本研究为钛合金gmaw基DED的工程应用提供了新的视角和指导。

{"title":"Cathode jet and columnar grain suppression in oscillating arc-wire directed energy deposition of titanium alloy","authors":"Kang Sun , Xiao Xiao , Shigeaki Uchida , Pengkang Zhao , Dongsheng Wu , Hisaya Komen , Ning Ma , Keke Zhang , Manabu Tanaka , Huijun Li","doi":"10.1016/j.jmatprotec.2026.119215","DOIUrl":"10.1016/j.jmatprotec.2026.119215","url":null,"abstract":"<div><div>As titanium is a thermionic cathode material, strong cathode jet can easily be caused by gas metal arc welding (GMAW)-based directed energy deposition (DED) of titanium alloys. Additionally, during the DED process, coarse columnar grains are prone to form, which severely affects the performance of the deposited titanium components. Therefore, it remains a challenge to fabricate high-performance titanium alloy components using GMAW-based DED. In this work, these obstacles can be overcome using an oscillating arc. Additionally, the influencing mechanisms of the oscillating arc on the cathode jet, droplet transfer, molten pool flow, microstructure, and mechanical properties were investigated. Experimental and simulation results indicated that the metal vapor near the welding wire in conventional GMAW-based DED was primarily composed of Ti ion (Ti Ⅱ) particles, while the cathode jet was mainly composed of Ti atom (Ti Ⅰ) particles. The oscillating arc reduced the molten pool temperature and caused the cathode jet to move away from the droplet. It also shifted the peak intensity of Ti atom particles from the molten pool to the welding wire, while promoting the ionization of a large number of Ti atom particles into Ti ion particles in the cathode jet region. The oscillating arc also promoted convection in the molten pool and altered the flow patterns, which increased the cooling rate and thereby refining the β and α grains. Oscillating cold metal transfer (CMT)-based DED significantly improved the mechanical properties of Ti6Al4V alloy. This work provides new perspectives and guidance for the engineering applications of GMAW-based DED of titanium alloys.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119215"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146035332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correlation between microstructure and residual stress formation in friction stir welded armor steels characterized by neutron diffraction 用中子衍射表征搅拌摩擦焊接装甲钢的显微组织与残余应力形成的关系

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-05 DOI: 10.1016/j.jmatprotec.2026.119198

Jhoan Guzman , Kaue C. Riffel , Martin McDonnell , Jeffrey Bunn , Andrew Payzant , Doug Kyle , Antonio J. Ramirez

Friction stir welding (FSW) is a solid-state joining process that minimizes the heat-affected zone (HAZ) compared with fusion-based arc welding, making it well suited for joining martensitic armor steels where hardness and ballistic resistance are critical. This study investigates residual stress formation in three defect-free FSW butt-joint configurations relevant to armored-vehicle fabrication: similar rolled homogeneous armor (RHA–RHA, Case 1), similar high-hardness armor (HHA–HHA, Case 2), and dissimilar HHA–RHA (Case 3) joints produced under temperature-controlled conditions (770 °C). Neutron diffraction was employed to quantify the magnitude and spatial distribution of residual stresses in the longitudinal, transverse, and normal directions and to correlate them with weld microstructure and hardness. Tensile residual stresses were concentrated in the softened HAZ, reaching approximately 300 MPa for Case 2 and 400 MPa for Case 1 (≈50–70 % of the base-metal yield strength; ∼581 MPa for RHA and ∼566 MPa for HHA), while compressive residual stresses dominated the stir zone. The spatial extent of tensile stresses scaled with the width of the softened HAZ, which was largest in the dissimilar HHA–RHA joint and smallest in the HHA–HHA joint. Full-width-at-half-maximum (FWHM) analysis revealed low microstrain in overtempered HAZ regions and high microstrain in the stir zone associated with severe plastic deformation and fresh martensite formation. This work demonstrates that residual stress evolution in FSW of martensitic armor steels is governed not primarily by peak temperature or thermal contraction, as inferred from fusion-welding analogies, but by the competition between transformation-induced volumetric expansion and tempering-induced stress relaxation. The relative dominance of these mechanisms is shown to depend on alloy hardenability and local thermal history, leading to more extensive HAZ softening and broader tensile stress regions in the lower-hardenability RHA steel. These findings establish a transferable mechanistic framework for optimizing solid-state joining strategies in high-strength steels and other transformation-hardening alloys beyond armor applications.

搅拌摩擦焊（FSW）是一种固态连接工艺，与基于熔焊的电弧焊相比，它可以最大限度地减少热影响区（HAZ），使其非常适合连接硬度和抗弹道性至关重要的马氏体装甲钢。本研究研究了与装甲车辆制造相关的三种无缺陷FSW对接配置的残余应力形成：在温度控制条件下（770°C）生产的类似轧制均匀装甲（rhaa - rha，案例1）、类似高硬度装甲（HHA-HHA，案例2）和不同的HHA-RHA（案例3）接头。采用中子衍射法定量分析了焊缝纵向、横向和法向残余应力的大小和空间分布，并将其与焊缝显微组织和硬度联系起来。拉伸残余应力集中在软化热区，情况2和情况1分别达到约300 MPa和400 MPa(≈母材屈服强度的50-70 %；RHA和HHA分别为~ 581 MPa和~ 566 MPa)，而残余压应力在搅拌区占主导地位。拉伸应力的空间范围与软化热区宽度成比例，不同类型的ha - rha接头拉伸应力最大，ha - hha接头拉伸应力最小。半最大全宽度（FWHM）分析显示，过热回火热影响区微应变低，搅拌区微应变高，伴有严重的塑性变形和新马氏体形成。这项工作表明，马氏体装甲钢的FSW残余应力演变主要不是由熔焊类比推断的峰值温度或热收缩控制，而是由变形引起的体积膨胀和回火引起的应力松弛之间的竞争决定的。这些机制的相对优势取决于合金的淬透性和局部热历史，导致更广泛的热影响区软化和更宽的拉应力区域在淬透性较低的RHA钢。这些发现为优化高强度钢和其他相变硬化合金的固态连接策略建立了可转移的机制框架。

{"title":"Correlation between microstructure and residual stress formation in friction stir welded armor steels characterized by neutron diffraction","authors":"Jhoan Guzman , Kaue C. Riffel , Martin McDonnell , Jeffrey Bunn , Andrew Payzant , Doug Kyle , Antonio J. Ramirez","doi":"10.1016/j.jmatprotec.2026.119198","DOIUrl":"10.1016/j.jmatprotec.2026.119198","url":null,"abstract":"<div><div>Friction stir welding (FSW) is a solid-state joining process that minimizes the heat-affected zone (HAZ) compared with fusion-based arc welding, making it well suited for joining martensitic armor steels where hardness and ballistic resistance are critical. This study investigates residual stress formation in three defect-free FSW butt-joint configurations relevant to armored-vehicle fabrication: similar rolled homogeneous armor (RHA–RHA, Case 1), similar high-hardness armor (HHA–HHA, Case 2), and dissimilar HHA–RHA (Case 3) joints produced under temperature-controlled conditions (770 °C). Neutron diffraction was employed to quantify the magnitude and spatial distribution of residual stresses in the longitudinal, transverse, and normal directions and to correlate them with weld microstructure and hardness. Tensile residual stresses were concentrated in the softened HAZ, reaching approximately 300 MPa for Case 2 and 400 MPa for Case 1 (≈50–70 % of the base-metal yield strength; ∼581 MPa for RHA and ∼566 MPa for HHA), while compressive residual stresses dominated the stir zone. The spatial extent of tensile stresses scaled with the width of the softened HAZ, which was largest in the dissimilar HHA–RHA joint and smallest in the HHA–HHA joint. Full-width-at-half-maximum (FWHM) analysis revealed low microstrain in overtempered HAZ regions and high microstrain in the stir zone associated with severe plastic deformation and fresh martensite formation. This work demonstrates that residual stress evolution in FSW of martensitic armor steels is governed not primarily by peak temperature or thermal contraction, as inferred from fusion-welding analogies, but by the competition between transformation-induced volumetric expansion and tempering-induced stress relaxation. The relative dominance of these mechanisms is shown to depend on alloy hardenability and local thermal history, leading to more extensive HAZ softening and broader tensile stress regions in the lower-hardenability RHA steel. These findings establish a transferable mechanistic framework for optimizing solid-state joining strategies in high-strength steels and other transformation-hardening alloys beyond armor applications.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119198"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Liquid-bridge regulation in femtosecond laser-assisted meniscus-confined electrodeposition 飞秒激光辅助半月板约束电沉积中的液桥调节

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-29 DOI: 10.1016/j.jmatprotec.2026.119237

Wanfei Ren , Hao Jiang , Wanfei Ren , Zhaoqiang Zou , Ningqian Tang , Pingmei Ming

Complex metal microstructures hold significant application potential in aerospace and biomedical engineering, yet their fabrication is hindered by critical challenges, particularly in achieving ultra-precision machining and realizing precise regulation of structural contours and surface morphologies at the micrometer scale. To address these issues, this study proposes an innovative femtosecond laser-assisted liquid-bridge regulation strategy for the high-quality and regulable fabrication of metal microstructures via electrodeposition. The core scientific advantage of this approach lies in its utilization of the femtosecond laser-induced photothermal effect, which enables active and non-contact regulation of the liquid-bridge contour a key breakthrough for precise regulation over the dimensions of deposited structures. Leveraging this regulable liquid-bridge regulation strategy, a variety of complex three-dimensional (3D) metal microstructures have been successfully fabricated. Microscopic characterization confirms that the fabricated microstructures possess dense interiors free of macroscopic defects; furthermore, the in-situ formation of nanocrystals and nanotwins endows these structures with excellent mechanical properties. This work provides a novel technical route for the dynamic regulation of electrodeposited structure dimensions, thereby substantially advancing the manufacturing capacity for complex metal microstructures and offering valuable insights for the broader research community in related fields.

复杂的金属微结构在航空航天和生物医学工程中具有重要的应用潜力，但它们的制造受到关键挑战的阻碍，特别是在实现超精密加工和实现微米尺度上结构轮廓和表面形态的精确调节方面。为了解决这些问题，本研究提出了一种创新的飞秒激光辅助液桥调节策略，用于通过电沉积高质量和可调节的金属微结构制造。该方法的核心科学优势在于它利用了飞秒激光诱导的光热效应，使液桥轮廓的主动和非接触调节成为精确调节沉积结构尺寸的关键突破。利用这种可调节的液桥调节策略，已经成功地制造了各种复杂的三维（3D）金属微结构。微观表征证实，制备的微结构具有致密的内部，没有宏观缺陷；此外，纳米晶和纳米孪晶的原位形成使这些结构具有优异的力学性能。这项工作为电沉积结构尺寸的动态调节提供了一条新的技术路线，从而大大提高了复杂金属微结构的制造能力，并为相关领域的广泛研究提供了有价值的见解。

{"title":"Liquid-bridge regulation in femtosecond laser-assisted meniscus-confined electrodeposition","authors":"Wanfei Ren , Hao Jiang , Wanfei Ren , Zhaoqiang Zou , Ningqian Tang , Pingmei Ming","doi":"10.1016/j.jmatprotec.2026.119237","DOIUrl":"10.1016/j.jmatprotec.2026.119237","url":null,"abstract":"<div><div>Complex metal microstructures hold significant application potential in aerospace and biomedical engineering, yet their fabrication is hindered by critical challenges, particularly in achieving ultra-precision machining and realizing precise regulation of structural contours and surface morphologies at the micrometer scale. To address these issues, this study proposes an innovative femtosecond laser-assisted liquid-bridge regulation strategy for the high-quality and regulable fabrication of metal microstructures via electrodeposition. The core scientific advantage of this approach lies in its utilization of the femtosecond laser-induced photothermal effect, which enables active and non-contact regulation of the liquid-bridge contour a key breakthrough for precise regulation over the dimensions of deposited structures. Leveraging this regulable liquid-bridge regulation strategy, a variety of complex three-dimensional (3D) metal microstructures have been successfully fabricated. Microscopic characterization confirms that the fabricated microstructures possess dense interiors free of macroscopic defects; furthermore, the in-situ formation of nanocrystals and nanotwins endows these structures with excellent mechanical properties. This work provides a novel technical route for the dynamic regulation of electrodeposited structure dimensions, thereby substantially advancing the manufacturing capacity for complex metal microstructures and offering valuable insights for the broader research community in related fields.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119237"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146074200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fast shot speed–dependent defect evolution in high-pressure die casting: Coupled roles of externally solidified crystals and cavity-formed α-Al 高压压铸中快射速缺陷演化：外部凝固晶体与空腔形成α-Al的耦合作用

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-23 DOI: 10.1016/j.jmatprotec.2026.119228

Lei Liu , Guantao Wang , Kai Zhao , Kaiyang Li , Yanqiang Li , Huanyue Zhang , Tao Zhang , Ying Fu , Zhirou Zhang , Enyu Guo , Huijun Kang , Zongning Chen , Jianru Fang , Tongmin Wang

Microstructural inhomogeneity and associated mechanical property fluctuations are inherent challenges in high-pressure die casting (HPDC), with origins difficult to elucidate due to coupled solidification and melt flow. In this study, the microstructural response of an HPDC AlSi10MnMg alloy to varying fast shot speeds was investigated using a TiB₂-assisted strategy to modify nucleation behavior in the shot sleeve and die cavity, enabling decoupling of the roles of externally solidified crystals (ESCs) and cavity-formed α-Al ((α-Al)_II) in defect formation. The results show that ESCs exhibit opposite responses to increasing fast shot speed. When ESCs nucleate near the shot sleeve wall, higher fast shot speed reduces ESCs content and size, whereas when ESCs are more uniformly dispersed in the melt, increasing fast shot speed promotes their transport into the die cavity, resulting in increased ESCs content. Under thermal-gradient-dominated solidification in die cavity, increasing fast shot speed leads to an inward shift and widening of segregation bands, accompanied by a reduced porosity volume fraction and increased pore number density. In contrast, when heterogeneous nucleation in the die cavity is promoted by TiB₂ addition, segregation-band position remains stable with band widening, while both porosity volume fraction and pore number density decrease, even though ESCs content increases. These defect evolutions are associated with systematic variations in strength and ductility. This work presents a process-based perspective for defect control in HPDC by decoupling microstructural variables under coupled melt flow and solidification, which may extend to other forming processes where flow and solidification are coupled.

显微组织不均匀性和相关的力学性能波动是高压压铸（HPDC）的固有挑战，由于凝固和熔体流动的耦合，其起源难以阐明。在这项研究中，采用tib2辅助策略，研究了HPDC AlSi10MnMg合金对不同快速射速的微观组织响应，以改变射套和模腔中的形核行为，使外部凝固晶体（ESCs）和腔内形成的α-Al （(α-Al)II）在缺陷形成中的作用解耦。结果表明，ESCs随着快射速度的增加表现出相反的反应。当ESCs在喷丸套壁附近成核时，高的快射速度降低了ESCs的含量和尺寸，而当ESCs在熔体中分布更均匀时，快射速度的增加促进了ESCs向模腔的迁移，从而导致ESCs含量的增加。在热梯度主导的模腔内凝固过程中，随着快射速度的增加，偏析带向内移动和扩大，孔隙体积分数降低，孔隙数密度增加。而当TiB2的加入促进模腔内非均相形核时，尽管ESCs含量增加，但偏析带位置保持稳定，而孔隙体积分数和孔数密度均降低。这些缺陷的演变与强度和延性的系统变化有关。本研究提出了一种基于过程的视角，通过解耦熔体流动和凝固耦合下的微观结构变量来控制高压直流成形过程中的缺陷，这可能扩展到其他流动和凝固耦合的成形过程中。

{"title":"Fast shot speed–dependent defect evolution in high-pressure die casting: Coupled roles of externally solidified crystals and cavity-formed α-Al","authors":"Lei Liu , Guantao Wang , Kai Zhao , Kaiyang Li , Yanqiang Li , Huanyue Zhang , Tao Zhang , Ying Fu , Zhirou Zhang , Enyu Guo , Huijun Kang , Zongning Chen , Jianru Fang , Tongmin Wang","doi":"10.1016/j.jmatprotec.2026.119228","DOIUrl":"10.1016/j.jmatprotec.2026.119228","url":null,"abstract":"<div><div>Microstructural inhomogeneity and associated mechanical property fluctuations are inherent challenges in high-pressure die casting (HPDC), with origins difficult to elucidate due to coupled solidification and melt flow. In this study, the microstructural response of an HPDC AlSi10MnMg alloy to varying fast shot speeds was investigated using a TiB<sub>2</sub>-assisted strategy to modify nucleation behavior in the shot sleeve and die cavity, enabling decoupling of the roles of externally solidified crystals (ESCs) and cavity-formed α-Al ((α-Al)<sub>II</sub>) in defect formation. The results show that ESCs exhibit opposite responses to increasing fast shot speed. When ESCs nucleate near the shot sleeve wall, higher fast shot speed reduces ESCs content and size, whereas when ESCs are more uniformly dispersed in the melt, increasing fast shot speed promotes their transport into the die cavity, resulting in increased ESCs content. Under thermal-gradient-dominated solidification in die cavity, increasing fast shot speed leads to an inward shift and widening of segregation bands, accompanied by a reduced porosity volume fraction and increased pore number density. In contrast, when heterogeneous nucleation in the die cavity is promoted by TiB<sub>2</sub> addition, segregation-band position remains stable with band widening, while both porosity volume fraction and pore number density decrease, even though ESCs content increases. These defect evolutions are associated with systematic variations in strength and ductility. This work presents a process-based perspective for defect control in HPDC by decoupling microstructural variables under coupled melt flow and solidification, which may extend to other forming processes where flow and solidification are coupled.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119228"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146034900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In situ surface rejuvenation and plasticity enhancement of Zr-based bulk metallic glass by high-speed cutting 高速切削zr基大块金属玻璃的原位表面回春及塑性增强

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-03-01 Epub Date: 2026-01-29 DOI: 10.1016/j.jmatprotec.2026.119232

Feng Ding , Pingjun Tao , Tao Zhang , Zijian Lai , Hongye Wu , Jun Wang , Lijuan Zheng , Xi Shen , Chengyong Wang

Zirconium-based (Zr-based) bulk metallic glasses (BMGs) are promising structural materials, but their application is hindered by their intrinsic brittleness, which arises from shear localization. This work presents an in situ surface engineering strategy that simultaneously shapes and functionally enhances Zr-based BMGs by harnessing the strong thermomechanical coupling associated with high-speed cutting. It is demonstrated that even at cutting speeds up to1600 m/min, high-speed cutting kinetically suppresses crystallization while spontaneously inducing structural rejuvenation in the machined subsurface. Multiscale characterization reveals that this rejuvenated state, characterized by reduced atomic ordering and increased free volume, drives a fundamental transition in the mechanical deformation mechanism: the volume of the shear transformation zone is refined, promoting a shift from highly localized shear banding to more homogeneous plasticity. Consequently, the engineered subsurface exhibits dramatically enhanced damage tolerance, with both plastic instability strain and energy absorption capacity prior to failure doubled compared to the as-cast state. This study establishes clear process–structure–property relationships, demonstrating that high-speed cutting is a versatile in situ manufacturing platform for tailoring the functional surface properties of BMGs. This approach bridges geometric shaping with property engineering, offering an efficient route for fabricating high-performance BMG components for advanced engineering applications.

锆基大块金属玻璃（Zr-based bulk metallic glass, bmg）是一种很有前途的结构材料，但由于剪切局部化而产生的固有脆性阻碍了其应用。这项工作提出了一种原位表面工程策略，通过利用与高速切削相关的强热-机械耦合，同时塑造和增强zr基bmg的功能。结果表明，即使在高达1600 m/min的切削速度下，高速切削在动力学上抑制了结晶，同时自发地诱导了加工亚表面的结构再生。多尺度表征表明，这种以原子有序度降低和自由体积增加为特征的恢复状态，推动了力学变形机制的根本转变：剪切转变区的体积被细化，促进了从高度局部剪切带向更均匀塑性的转变。因此，与铸态相比，工程亚表面表现出显著增强的损伤容忍度，破坏前的塑性不稳定应变和能量吸收能力都增加了一倍。该研究建立了清晰的工艺-结构-性能关系，证明高速切削是一种多功能的原位制造平台，可用于定制bmg的功能表面特性。这种方法将几何形状与性能工程相结合，为制造高性能的BMG组件提供了有效的途径，用于先进的工程应用。

{"title":"In situ surface rejuvenation and plasticity enhancement of Zr-based bulk metallic glass by high-speed cutting","authors":"Feng Ding , Pingjun Tao , Tao Zhang , Zijian Lai , Hongye Wu , Jun Wang , Lijuan Zheng , Xi Shen , Chengyong Wang","doi":"10.1016/j.jmatprotec.2026.119232","DOIUrl":"10.1016/j.jmatprotec.2026.119232","url":null,"abstract":"<div><div>Zirconium-based (Zr-based) bulk metallic glasses (BMGs) are promising structural materials, but their application is hindered by their intrinsic brittleness, which arises from shear localization. This work presents an <em>in situ</em> surface engineering strategy that simultaneously shapes and functionally enhances Zr-based BMGs by harnessing the strong thermomechanical coupling associated with high-speed cutting. It is demonstrated that even at cutting speeds up to1600 m/min, high-speed cutting kinetically suppresses crystallization while spontaneously inducing structural rejuvenation in the machined subsurface. Multiscale characterization reveals that this rejuvenated state, characterized by reduced atomic ordering and increased free volume, drives a fundamental transition in the mechanical deformation mechanism: the volume of the shear transformation zone is refined, promoting a shift from highly localized shear banding to more homogeneous plasticity. Consequently, the engineered subsurface exhibits dramatically enhanced damage tolerance, with both plastic instability strain and energy absorption capacity prior to failure doubled compared to the as-cast state. This study establishes clear process–structure–property relationships, demonstrating that high-speed cutting is a versatile in situ manufacturing platform for tailoring the functional surface properties of BMGs. This approach bridges geometric shaping with property engineering, offering an efficient route for fabricating high-performance BMG components for advanced engineering applications.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"349 ","pages":"Article 119232"},"PeriodicalIF":7.5,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146074199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Crack-free additive manufacturing of Ni-based superalloy IN713LC with enhanced performance via high-temperature thermal field assistance ni基高温合金IN713LC的高温热场辅助无裂纹增材制造

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-02-01 Epub Date: 2025-12-05 DOI: 10.1016/j.jmatprotec.2025.119174

Shuai Liu , Xin Wen , Changsheng Liu , Zhikang Xia , Yongqiang Wang , Chao Yuan

High-temperature thermal-field-assisted additive manufacturing (AM) has been applied to several γ′-rich Ni-based superalloys, yet a generalizable parameter selection scheme, quantitative defect regime mapping, and fundamental understanding of microstructural evolution remain elusive. Here, IN713LC is used as a representative alloy and fabricated via induction-heating-assisted laser directed energy deposition (IH-LDED) to address these gaps. Crack-free and dense builds were achieved at process temperatures between the γ′ precipitation threshold and the solidus, using 70–80 % of the theoretical melting energy density. A crack-type competition mechanism, governed by the coupling of temperature and energy density, was revealed. Elevated temperatures promoted γ′ homogenization and eliminated γ/γ′ eutectic, suppressing liquation cracking and preventing ductility-dip cracking. Strain-age cracking was dominated by notch effects, transformation stresses, or thermal stresses under different conditions. Low energy input caused local oxidation, whereas super-solidus temperatures triggered rapid semi-solid oxidation and a novel feedback loop, both leading to oxidation-induced cracking. As process temperature increased, solute-driven differential lattice expansion modified γ/γ′ misfit from 1.1 % at 1100°C to −4.1 % at 1200°C, strengthening the coherent strain field. This shifted γ′–dislocation interactions from long-range cooperative shearing to short-range shearing and Orowan bypass, enabling tailored strength–ductility combinations. These findings establish a generic process–defect–microstructure–performance framework, offering mechanistic and transferable insights into additive manufacturing of non-weldable superalloys (e.g., performance customization and quantitative defect analysis).

高温热场辅助增材制造（AM）已经应用于几种富含γ′的镍基高温合金，但可推广的参数选择方案、定量缺陷状态映射以及对微观组织演变的基本理解仍然难以捉摸。本文以IN713LC为代表合金，通过感应加热辅助激光定向能沉积（ih - lcd）来解决这些空白。在γ′析出阈值和固相之间的工艺温度下，使用70-80 %的理论熔化能密度，实现了无裂纹和致密的构建。揭示了一种由温度和能量密度耦合控制的裂纹型竞争机制。高温促进了γ′均质化，消除了γ/γ′共晶，抑制了液化开裂，防止了塑性倾斜开裂。在不同条件下，裂纹主要由缺口效应、相变应力或热应力控制。低能量输入导致局部氧化，而超固体温度引发快速半固体氧化和一个新的反馈回路，两者都导致氧化诱导的开裂。随着工艺温度的升高，溶质驱动的微分晶格膨胀使γ/γ′失配从1100℃时的1.1 %增加到1200℃时的−4.1 %，增强了相干应变场。这将γ′-位错相互作用从远程协同剪切转变为短程剪切和Orowan旁路，实现了量身定制的强度-塑性组合。这些发现建立了一个通用的工艺-缺陷-微观结构-性能框架，为不可焊接高温合金的增材制造（例如，性能定制和定量缺陷分析）提供了机理和可转移的见解。

{"title":"Crack-free additive manufacturing of Ni-based superalloy IN713LC with enhanced performance via high-temperature thermal field assistance","authors":"Shuai Liu , Xin Wen , Changsheng Liu , Zhikang Xia , Yongqiang Wang , Chao Yuan","doi":"10.1016/j.jmatprotec.2025.119174","DOIUrl":"10.1016/j.jmatprotec.2025.119174","url":null,"abstract":"<div><div>High-temperature thermal-field-assisted additive manufacturing (AM) has been applied to several γ′-rich Ni-based superalloys, yet a generalizable parameter selection scheme, quantitative defect regime mapping, and fundamental understanding of microstructural evolution remain elusive. Here, IN713LC is used as a representative alloy and fabricated via induction-heating-assisted laser directed energy deposition (IH-LDED) to address these gaps. Crack-free and dense builds were achieved at process temperatures between the γ′ precipitation threshold and the solidus, using 70–80 % of the theoretical melting energy density. A crack-type competition mechanism, governed by the coupling of temperature and energy density, was revealed. Elevated temperatures promoted γ′ homogenization and eliminated γ/γ′ eutectic, suppressing liquation cracking and preventing ductility-dip cracking. Strain-age cracking was dominated by notch effects, transformation stresses, or thermal stresses under different conditions. Low energy input caused local oxidation, whereas super-solidus temperatures triggered rapid semi-solid oxidation and a novel feedback loop, both leading to oxidation-induced cracking. As process temperature increased, solute-driven differential lattice expansion modified γ/γ′ misfit from 1.1 % at 1100°C to −4.1 % at 1200°C, strengthening the coherent strain field. This shifted γ′–dislocation interactions from long-range cooperative shearing to short-range shearing and Orowan bypass, enabling tailored strength–ductility combinations. These findings establish a generic process–defect–microstructure–performance framework, offering mechanistic and transferable insights into additive manufacturing of non-weldable superalloys (e.g., performance customization and quantitative defect analysis).</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"348 ","pages":"Article 119174"},"PeriodicalIF":7.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145749018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Role of laser beam shape and energy density in modulating surface quality, porosity, microstructure, and mechanical properties of PBF-LB/M Ti-6Al-4V 激光束形状和能量密度对PBF-LB/M Ti-6Al-4V表面质量、孔隙率、微观结构和力学性能的影响

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-02-01 Epub Date: 2026-01-03 DOI: 10.1016/j.jmatprotec.2026.119197

Abid Ullah , Alexander E. Medvedev , Dirk Herzog , Andrey Molotnikov , Tingting Liu , Ingomar Kelbassa , Milan Brandt

Beam shaping has recently gained attention as a means to mitigate the thermal gradients and melt-pool instabilities associated with conventional Gaussian beams in laser powder bed fusion (PBF-LB/M), which often lead to surface roughness, defects, and microstructural inconsistency. This study examines the effects of different beam shapes and volumetric energy densities (VEDs) on the surface quality, porosity, microstructure, and mechanical response of Ti-6Al-4V. Cubic specimens were fabricated on an Aconity MIDI+ system using Gaussian, core-ring, and ring beam profiles over a VED range of 78–341 J/mm³ . The results show that beam shaping with optimized VED reduces porosity, refines microstructure, and enhances mechanical performance. The Gaussian beam performed well at low VEDs (≤130 J/mm³) but exhibited increased surface roughness and keyhole porosity at higher energy inputs (≥150 J/mm³), whereas the ring-based beams initially showed higher porosity at low VEDs but achieved ∼99.97 % relative density and smoother surfaces at higher VEDs. The ring beam promoted stable conduction-mode melting, continuous prior-β grain growth, refined α′ martensitic microstructures, and strong crystallographic texture. From a mechanical perspective, Vickers hardness values (370–400 HV) correlated with the observed microstructural features. In addition, the Gaussian beam exhibited higher indicative strength at low VEDs but deteriorated with increasing energy input, whereas the ring beam showed the opposite trend, reaching an ultimate tensile strength of 1192 MPa and ∼21 % ductility under optimal conditions. Beam behavior was further evaluated using areal energy density (AED) normalized to the melt-pool width, indicating that melt-pool stability and the resulting surface quality, porosity, and microstructural evolution are primarily influenced by the spatial distribution of laser energy rather than nominal energy metrics alone. These findings provide a physical basis for laser beam shaping as an effective approach to broaden the stable processing window and achieve defect-free, texture-controlled Ti-6Al-4V components.

在激光粉末床熔合（PBF-LB/M）中，由于传统高斯光束导致表面粗糙度、缺陷和微观结构不一致，因此光束整形作为一种缓解热梯度和熔池不稳定性的手段受到了人们的关注。本研究考察了不同光束形状和体积能量密度（VEDs）对Ti-6Al-4V表面质量、孔隙率、微观结构和力学响应的影响。在Aconity MIDI+ 系统上，采用高斯光束、芯环光束和环形光束剖面，在78-341 J/mm³ 范围内制备立方试样。结果表明：优化后的VED梁形可以降低孔隙率，改善微观结构，提高力学性能。高斯光束在低VEDs下表现良好（≤130 J/mm³），但在更高的能量输入（≥150 J/mm³）下，表面粗糙度和锁孔孔隙度增加，而环基光束在低VEDs下最初表现出更高的孔隙度，但在更高的VEDs下获得了~ 99.97 %的相对密度和更光滑的表面。环形束促进了稳定的导电模式熔化、连续的-β晶粒生长、细化的α′马氏体组织和强的晶体织构。从力学角度看，维氏硬度值（370-400 HV）与观察到的显微组织特征相关。此外，高斯梁在低VEDs下表现出较高的指示强度，但随着能量输入的增加而恶化，而环梁表现出相反的趋势，在最佳条件下达到1192 MPa的极限抗拉强度和~ 21 %的塑性。利用面能密度（AED）对熔池宽度进行归一化，进一步评估了光束行为，表明熔池稳定性以及由此产生的表面质量、孔隙度和微观结构演变主要受到激光能量空间分布的影响，而不仅仅是标称能量指标。这些发现为激光束整形提供了物理基础，作为扩大稳定加工窗口和实现无缺陷、纹理控制的Ti-6Al-4V组件的有效方法。

{"title":"Role of laser beam shape and energy density in modulating surface quality, porosity, microstructure, and mechanical properties of PBF-LB/M Ti-6Al-4V","authors":"Abid Ullah , Alexander E. Medvedev , Dirk Herzog , Andrey Molotnikov , Tingting Liu , Ingomar Kelbassa , Milan Brandt","doi":"10.1016/j.jmatprotec.2026.119197","DOIUrl":"10.1016/j.jmatprotec.2026.119197","url":null,"abstract":"<div><div>Beam shaping has recently gained attention as a means to mitigate the thermal gradients and melt-pool instabilities associated with conventional Gaussian beams in laser powder bed fusion (PBF-LB/M), which often lead to surface roughness, defects, and microstructural inconsistency. This study examines the effects of different beam shapes and volumetric energy densities (VEDs) on the surface quality, porosity, microstructure, and mechanical response of Ti-6Al-4V. Cubic specimens were fabricated on an Aconity MIDI+ system using Gaussian, core-ring, and ring beam profiles over a VED range of 78–341 J/mm³ . The results show that beam shaping with optimized VED reduces porosity, refines microstructure, and enhances mechanical performance. The Gaussian beam performed well at low VEDs (≤130 J/mm³) but exhibited increased surface roughness and keyhole porosity at higher energy inputs (≥150 J/mm³), whereas the ring-based beams initially showed higher porosity at low VEDs but achieved ∼99.97 % relative density and smoother surfaces at higher VEDs. The ring beam promoted stable conduction-mode melting, continuous prior-β grain growth, refined α′ martensitic microstructures, and strong crystallographic texture. From a mechanical perspective, Vickers hardness values (370–400 HV) correlated with the observed microstructural features. In addition, the Gaussian beam exhibited higher indicative strength at low VEDs but deteriorated with increasing energy input, whereas the ring beam showed the opposite trend, reaching an ultimate tensile strength of 1192 MPa and ∼21 % ductility under optimal conditions. Beam behavior was further evaluated using areal energy density (AED) normalized to the melt-pool width, indicating that melt-pool stability and the resulting surface quality, porosity, and microstructural evolution are primarily influenced by the spatial distribution of laser energy rather than nominal energy metrics alone. These findings provide a physical basis for laser beam shaping as an effective approach to broaden the stable processing window and achieve defect-free, texture-controlled Ti-6Al-4V components.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"348 ","pages":"Article 119197"},"PeriodicalIF":7.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145939266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fracture of ultrathin coating during micro-channel forming process of coated metallic sheet: Experiments and numerical prediction 涂层金属薄板微通道成形过程中超薄涂层的断裂：实验与数值预测

IF 7.5 2区材料科学 Q1 ENGINEERING, INDUSTRIAL

Journal of Materials Processing Technology

Pub Date : 2026-02-01 Epub Date: 2025-12-03 DOI: 10.1016/j.jmatprotec.2025.119164

Jilai Wang , Chuanzheng Li , Haotian Gong , Zhutian Xu , Yi Wan

The coating-then-forming process offers a promising route to improve the manufacturing efficiency of metallic bipolar plates in proton exchange membrane fuel cells. However, fracture of ultrathin coatings during forming presents a formidable challenge to the corrosion resistance of coated metallic sheets. To provide theoretical guidance for addressing this issue, this work investigates the coating fracture behavior during the micro-channel forming process through experiments and numerical analysis. Coating cracks were revealed to be concentrated within the fillet and flat regions of the channel ridge, highly sensitive to local strain levels governed by both channel geometry and substrate microstructure. Therefore, a full-field simulation methodology was developed to predict the coating fracture during forming, balancing between computational efficiency with accuracy. Within this numerical framework, hybrid modeling of the metallic sheet substrate was employed, combining local implementation of crystal plasticity in the critical region with homogeneous materials elsewhere. For coating on the critical region, varying failure parameters correlated with substrate microstructure were determined by the microscopic fracture mechanism. Experimental validation confirms that the developed model can precisely predict both coating fractures and formed profiles, notably achieving an 80 % accuracy improvement in crack density compared to conventional approaches. Based on the simulation results, process windows were established to correlate coating fracture and channel geometry with forming parameters, thereby guiding optimization toward the minimization of crack density under geometrical constraints. Following parameter optimization, coating cracks were successfully eliminated at the flat region, demonstrating an effective strategy for maintaining the corrosion resistance after forming.

先涂覆后成形工艺为提高质子交换膜燃料电池金属双极板的制造效率提供了一条很有前途的途径。然而，超薄涂层在成形过程中的断裂对涂层金属板的耐腐蚀性能提出了严峻的挑战。为了为解决这一问题提供理论指导，本工作通过实验和数值分析研究了微通道成形过程中涂层的断裂行为。涂层裂纹集中在沟道脊的角状和平坦区域内，对沟道几何形状和衬底微观结构控制的局部应变水平高度敏感。因此，为了在计算效率和精度之间取得平衡，开发了一种预测成形过程中涂层断裂的全场模拟方法。在此数值框架内，采用金属板衬底的混合建模，将临界区域的局部晶体塑性实现与其他地方的均匀材料相结合。对于临界区域的涂层，由微观断裂机制决定了与基体组织相关的不同失效参数。实验验证证实，所开发的模型可以精确预测涂层裂缝和成形轮廓，与传统方法相比，裂缝密度的精度提高了80% %。基于仿真结果，建立工艺窗口，将涂层断口和通道几何形状与成形参数关联起来，从而指导优化在几何约束下实现裂纹密度的最小化。通过参数优化，涂层在平面区域的裂纹被成功消除，证明了一种有效的策略来保持成型后的耐腐蚀性。

{"title":"Fracture of ultrathin coating during micro-channel forming process of coated metallic sheet: Experiments and numerical prediction","authors":"Jilai Wang , Chuanzheng Li , Haotian Gong , Zhutian Xu , Yi Wan","doi":"10.1016/j.jmatprotec.2025.119164","DOIUrl":"10.1016/j.jmatprotec.2025.119164","url":null,"abstract":"<div><div>The coating-then-forming process offers a promising route to improve the manufacturing efficiency of metallic bipolar plates in proton exchange membrane fuel cells. However, fracture of ultrathin coatings during forming presents a formidable challenge to the corrosion resistance of coated metallic sheets. To provide theoretical guidance for addressing this issue, this work investigates the coating fracture behavior during the micro-channel forming process through experiments and numerical analysis. Coating cracks were revealed to be concentrated within the fillet and flat regions of the channel ridge, highly sensitive to local strain levels governed by both channel geometry and substrate microstructure. Therefore, a full-field simulation methodology was developed to predict the coating fracture during forming, balancing between computational efficiency with accuracy. Within this numerical framework, hybrid modeling of the metallic sheet substrate was employed, combining local implementation of crystal plasticity in the critical region with homogeneous materials elsewhere. For coating on the critical region, varying failure parameters correlated with substrate microstructure were determined by the microscopic fracture mechanism. Experimental validation confirms that the developed model can precisely predict both coating fractures and formed profiles, notably achieving an 80 % accuracy improvement in crack density compared to conventional approaches. Based on the simulation results, process windows were established to correlate coating fracture and channel geometry with forming parameters, thereby guiding optimization toward the minimization of crack density under geometrical constraints. Following parameter optimization, coating cracks were successfully eliminated at the flat region, demonstrating an effective strategy for maintaining the corrosion resistance after forming.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"348 ","pages":"Article 119164"},"PeriodicalIF":7.5,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145693103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0