Journal of Advanced Joining Processes最新文献_第6页

Investigation of the weld characteristics of AA6016-T4 friction stitch welds in overlap configuration and the influence of stitch length on static and fatigue strength 研究了AA6016-T4摩擦缝焊缝重叠结构的焊接特性及缝长对静强度和疲劳强度的影响

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-11-25 DOI: 10.1016/j.jajp.2025.100363

Dominik Walz, Stefan Weihe, Martin Werz

High-strength, age-hardenable aluminum alloys in car body construction challenge conventional joining methods — especially in mixed-material body structures, as fusion welding is prone to hot cracking and to hydrogen porosity. As a solid-state process, friction stir welding circumvents these challenges and typically produces joints with a higher strength than fusion welding, particularly in high-strength aluminum alloys. While friction stir spot welding guns are commercially available, the joints produced with them exhibit significantly lower strength compared to linear welds. To address this issue, a friction stir welding gun capable of producing short stitch welds was developed for a possible application in car body manufacturing.

This work investigates friction stitch welds in AA6016-T4 sheet overlap joints and quantifies how the stitch length influences static strength, fatigue performance, hardness, and microstructure, compared to a continuous friction stir welded (FSW) joint. Short stitch welds obtained the highest lap-shear strength, achieving up to 83% joint efficiency, while longer welds reached between 65% and 68%. Metallography confirmed overlap-specific features, such as cold-lap imperfections in the weld, and showed that tool reentry can locally fragment the oxide line and diminish cold-lap severity, improving static strength. The fatigue performance of the stitch welds was lower than that of the strongest static condition, with short stitches particularly susceptible to notch effects due to overlap-specific features and reentry-related porosity. In general, intersecting stitch welds can surpass continuous FSW in static strength, but fatigue optimization will require mitigating the severity of the cold lap and reentry imperfections, for example, through adapted tool and pin designs.

汽车车身结构中的高强度、可时效硬化铝合金挑战了传统的连接方法，特别是在混合材料车身结构中，因为熔焊容易产生热裂和氢孔隙。作为一种固态工艺，搅拌摩擦焊接避免了这些挑战，并且通常产生比熔焊更高强度的接头，特别是在高强度铝合金中。虽然搅拌摩擦点焊枪是市售的，但与直线焊接相比，用它们生产的接头强度明显较低。为了解决这一问题，开发了一种能够产生短缝焊缝的搅拌摩擦焊枪，有望在汽车车身制造中得到应用。本文研究了AA6016-T4板重叠接头的摩擦缝焊接，并量化了与连续搅拌摩擦焊（FSW）接头相比，摩擦缝长度对静态强度、疲劳性能、硬度和微观结构的影响。短缝焊缝获得了最高的搭接剪切强度，接头效率高达83%，而长缝焊缝的接头效率在65%至68%之间。金相图证实了重叠的特定特征，例如焊缝中的冷搭缺陷，并表明工具再入可以局部破坏氧化线，降低冷搭的严重程度，提高静态强度。缝焊缝的疲劳性能低于最强静态条件下的疲劳性能，由于重叠的特定特征和与再入孔相关的孔隙率，短缝焊缝特别容易受到缺口效应的影响。一般来说，交叉缝焊缝的静态强度可以超过连续FSW，但疲劳优化需要减轻冷搭接和再入缺陷的严重程度，例如，通过调整工具和销的设计。

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引用次数: 0

Comparative study of inertia and continuous drive friction welding processes based on equivalent energy input 基于等效能量输入的惯性与连续驱动摩擦焊接工艺对比研究

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-07-29 DOI: 10.1016/j.jajp.2025.100337

Carina Vauderwange , Dirk Lindenau , Heinz Palkowski , Hadi Mozaffari Jovein

Rotary friction welding can be performed using either continuous drive friction welding (CDFW) or inertia friction welding (IFW), which utilizes stored energy in a flywheel. Historically, these methods have distinct applications and geographic preferences: IFW is prevalent in the US, especially for superalloys, while CDFW is more common in Europe, focusing on automotive materials like steel and aluminum. This study presents a comparative analysis of both welding techniques using the same friction welding machine to minimize external variables. The free-machining steel AISI 1215, chosen for its banded microstructure, serves as the specimen material. The comparison is based on the same energetic input of 82.8 kJ to ensure consistency. However, IFW experienced significant losses due to internal friction, which further decelerated the spindle and reduced the effective weld energy to 68 kJ. Key findings include differences in deformation behavior and weld formation efficiency. CDFW exhibits a softer deformation, with principal shortening occurring during the forge phase due to axial force, resulting in large equiaxed inclusions in the weld zone. Additionally, less upset is generated with the same calculated energy input. In contrast, IFW demonstrates sharper deformation, with main shortening in the friction phase, achieving greater total upset. The combination of axial force and torque produces a spiralized material flow and finely dispersed inclusions due to high shear forces. These insights highlight the distinct advantages and characteristics of each welding technique, providing valuable information for their respective applications.

旋转摩擦焊可以使用连续驱动摩擦焊（CDFW）或惯性摩擦焊（IFW）进行，后者利用飞轮中存储的能量。从历史上看，这些方法有不同的应用和地理偏好：IFW在美国很普遍，特别是用于高温合金，而CDFW在欧洲更常见，主要用于钢铁和铝等汽车材料。本研究提出了一种比较分析两种焊接技术使用同一摩擦焊机，以尽量减少外部变量。自由加工钢AISI 1215，选择其带状组织，作为试样材料。为了保证一致性，比较是基于相同的能量输入82.8 kJ。然而，由于内摩擦，IFW经历了显著的损失，这进一步使主轴减速，并将有效焊接能量降低到68 kJ。主要发现包括变形行为和焊缝成形效率的差异。CDFW表现出较软的变形，主要缩短发生在锻造阶段，由于轴向力，导致焊缝区有大量等轴夹杂物。此外，在相同的计算能量输入下，产生的扰动更少。相比之下，IFW表现出更剧烈的变形，主要在摩擦阶段缩短，实现了更大的总变形。由于高剪切力，轴向力和扭矩的结合产生螺旋状的物料流和精细分散的夹杂物。这些见解突出了每种焊接技术的独特优势和特点，为各自的应用提供了有价值的信息。

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引用次数: 0

Comparison of the economic efficiency and sustainability of two debonding processes for structurally bonded sills 两种结构粘接工艺的经济效率和可持续性比较

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-07-25 DOI: 10.1016/j.jajp.2025.100332

Alex Jordan , Lucas Hermelingmeier , Julian Gilich , Gerson Meschut , Marco De Santis , Alexander Schlüter

In light of growing demands for resource efficiency and sustainability in vehicle engineering, the environmentally compatible separation of structural adhesive joints is gaining increasing relevance. This study presents a comparative analysis of two physically based debonding methods: the established hot-air process and a cryogenic cold process based on liquid nitrogen (LN₂). The primary objective is to assess the ecological impact and process-related sustainability of both approaches.

Experimental investigations were conducted on a component-representative triple-sheet structure that simulates common automotive flange joints. Thermal input was applied either by convective heating using a hot air gun or by direct cooling through a contact-based LN₂ tool. The resulting temperature profiles were recorded using spatially distributed thermocouples. Subsequently, the outer panel was selectively debonded to replicate a repair scenario, and the mechanical integrity of the remaining adhesive joint was evaluated through Mode I testing of l-shaped specimens. Process data served as input for an Life Cycle Assessment (LCA) according to DIN EN ISO 14,040.

The cryogenic method achieved a 40 % reduction in carbon footprint compared to the hot-air process (0.337 kg vs. 0.559 kg CO₂-equivalents), primarily due to its shorter process time and more efficient heat transfer. While the hot-air method’s impact is mainly driven by electrical energy use, that of the cold method stems from cryogenic media consumption. Notwithstanding certain disadvantages in specific impact categories, the LN₂-based process exhibits a superior overall ecological performance and signifies a promising solution for repair- and recycling-oriented adhesive separation in structural vehicle applications.

随着汽车工程对资源效率和可持续性的要求越来越高，结构粘接接头的环境兼容分离越来越重要。本研究对比分析了两种基于物理的脱粘方法：已建立的热空气法和基于液氮（LN2）的低温冷法。主要目标是评估这两种方法的生态影响和与过程有关的可持续性。以具有代表性的三板结构为研究对象，模拟了常见的汽车法兰连接。热输入可以通过热风枪对流加热，也可以通过接触式LN2工具直接冷却。利用空间分布的热电偶记录得到的温度分布。随后，有选择地剥离外面板以复制修复场景，并通过l形试件的I型测试评估剩余粘合接头的机械完整性。根据DIN EN ISO 14040，过程数据作为生命周期评估（LCA）的输入。与热空气法相比，深冷法的碳足迹减少了40% （0.337 kg对0.559 kg二氧化碳当量），这主要是由于其更短的工艺时间和更有效的传热。热空气法的影响主要是由电能的使用驱动的，而冷法的影响则源于低温介质的消耗。尽管在特定的影响类别中存在一定的缺点，但基于ln2的工艺表现出优越的整体生态性能，并标志着结构车辆应用中以修复和回收为导向的粘合剂分离的有希望的解决方案。

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引用次数: 0

Exploring the hybridization of wire-arc additive manufacturing and resistance spot welding 探索线弧增材制造与电阻点焊的融合

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-10-10 DOI: 10.1016/j.jajp.2025.100354

Maria R.F. Barros , Pedro M.S. Rosado , Rui F.V. Sampaio , João P.M. Pragana , Ivo M.F. Bragança , Carlos M.A. Silva , Paulo A.F. Martins

This paper explores a new hybrid manufacturing approach that combines wire-arc additive manufacturing (WAAM) with resistance spot welding (RSW). The approach integrates additively deposited materials with commercial sheets, which can serve as either supporting or functional elements. Experimental testing and finite element modelling allowed defining the weld lobe and optimizing key parameters such as electric current and welding time. Optimization was based on nugget shape, microstructure, and mechanical performance from destructive shear and peel tests. Two distinct joining modes were identified: symmetric and asymmetric weld nuggets, with the former exhibiting higher strength but requiring a higher heat input. A proof-of-concept prototype was developed to demonstrate the potential of this innovative hybrid manufacturing approach, combining WAAM, machining, forming, and RSW to fabricate complex, multi-thickness components with improved structural integrity.

本文探讨了一种将线弧增材制造（WAAM）与电阻点焊（RSW）相结合的新型混合制造方法。该方法将添加剂沉积材料与商业板材相结合，既可以作为支撑元素，也可以作为功能元素。通过实验测试和有限元建模，确定了焊缝瓣形，并优化了电流和焊接时间等关键参数。优化基于核块形状、微观结构以及破坏性剪切和剥离试验的力学性能。确定了两种不同的连接模式：对称和非对称焊块，前者具有更高的强度，但需要更高的热量输入。开发了一个概念验证原型，以展示这种创新的混合制造方法的潜力，将WAAM、加工、成形和RSW结合起来，制造复杂的、多厚度的部件，并提高结构完整性。

引用次数: 0

The effect of heat input on the residual stress distribution in gas-metal arc welding of carbon steel: Simulation and experimental methods 热输入对碳钢气-金属电弧焊残余应力分布的影响：模拟与实验方法

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-07-25 DOI: 10.1016/j.jajp.2025.100333

Amir Dadkhah , Mahmoud Sarkari Khorrami , Seyed Farshid Kashani-Bozorg , Reza Miresmaeili

A major challenge in fusion welding is the development of residual stresses and distortions, stemming primarily from non-uniform thermal cycles during welding. These stresses adversely influence fatigue life, corrosion resistance, and dimensional stability of engineering components. Heat input is a crucial parameter governing residual stress formation. Conventional experimental methods for residual stress determination are often time-consuming or destructive, making simulation an efficient alternative for stress prediction. This study assessed the effect of heat input on residual stress in the gas metal arc welding (GMAW) process through integrated simulation and hole-drilling measurements. For this purpose, A516 Gr70 steel plates were welded using the GMAW technique with varying heat inputs, both with and without a back welding. After characterizing microstructure and mechanical properties, residual stresses were quantified via the hole-drilling method. Numerical simulation employed Abaqus with the Goldak double-ellipsoid heat source model and element birth-and-death technique, with results validated against experimental data. The microhardness value of the weld zone produced by the lowest heat input was found to be ∼198 HV, with a microstructure dominated by pearlite and varying morphologies of ferrites. Simulation revealed peak residual stresses in the heat-affected zone (HAZ) and weld center across all heat inputs. The reduction in heat input and applying the back welding resulted in less tensile residual stresses in most areas and slightly increased compressive residual stresses in areas farther from the HAZ. Four-channel thermocouple measurements and numerical simulation provided detailed thermal analysis during welding, with simulated residual stresses showing 96 % agreement with hole-drilling results, validating both methodologies.

熔焊的一个主要挑战是残余应力和变形的发展，主要源于焊接过程中不均匀的热循环。这些应力对工程部件的疲劳寿命、耐腐蚀性和尺寸稳定性产生不利影响。热输入是控制残余应力形成的关键参数。传统的残余应力测定实验方法往往耗时或破坏性，使模拟成为应力预测的有效替代方法。本研究通过综合模拟和钻孔测量，评估了热输入对气体保护焊（GMAW）过程中残余应力的影响。为此，A516 Gr70钢板采用不同热量输入的GMAW技术焊接，有或没有背焊。在表征微观组织和力学性能后，通过钻孔法对残余应力进行量化。数值模拟采用Abaqus软件，采用Goldak双椭球热源模型和单元生死技术，并与实验数据进行了验证。最低热输入产生的焊缝区显微硬度值为~ 198 HV，显微组织以珠光体和不同形态的铁素体为主。模拟结果表明，热影响区（HAZ）和焊缝中心的残余应力峰值贯穿所有热输入。减少热输入和应用背焊导致大多数区域的拉伸残余应力较小，而远离热影响区区域的压残余应力略有增加。四通道热电偶测量和数值模拟提供了焊接过程中详细的热分析，模拟的残余应力与钻孔结果的一致性达到96%，验证了这两种方法。

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引用次数: 0

Modeling and simulation of inertia and continuous drive friction welding of AISI 1215 steel AISI 1215钢惯性与连续驱动摩擦焊接的建模与仿真

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-11-17 DOI: 10.1016/j.jajp.2025.100360

Carina Vauderwange , Dirk Lindenau , Heinz Palkowski , Hadi Mozaffari Jovein

To accurately simulate rotary friction welding (RFW), calibration of the material model and friction conditions is essential. This study focuses on developing a material model and simulation for RFW of AISI 1215 free-machining steel in the environment “virtua RFW”. Inertia (IFW) and continuous drive friction welding (CDFW) were physically performed with comparable energy inputs to calibrate the simulation. The aim of this study is to examine the calibration procedure in detail and subsequently perform a simulation-based process comparison of IFW and CDFW. For calibration, four material and friction factors were varied in an L16 Taguchi array. Different methods for evaluating simulation quality were assessed. Upset deviation and flash angle α measurement via image processing were determined to be the most suitable methods for evaluating the alignment between simulation and real welds. Optimal simulation parameters were identified for IFW, closely matching experimental results. Due to the velocity and pressure dependence of the friction behavior, a direct transfer of parameters to CDFW was not possible, requiring adjustments and regression analysis for accurate prediction. Optimized simulations showed differences in the thermomechanical behavior: IFW exhibited a steeper temperature gradient with a minimum cooling time t8/5 of 2.5 s and a double-wedge shape in the affected zone, while CDFW showed a broader, more uniform zone with a minimum cooling time t8/5 of 3 s. These findings improve the understanding of IFW and CDFW and provide calibrated simulation models that could facilitate more efficient process development.

为了准确地模拟旋转摩擦焊接（RFW），材料模型和摩擦条件的校准至关重要。本研究的重点是建立AISI 1215自由加工钢在“虚拟RFW”环境下的材料模型和RFW仿真。惯性焊接（IFW）和连续驱动摩擦焊接（CDFW）在物理上进行了比较的能量输入，以校准模拟。本研究的目的是详细检查校准程序，并随后对IFW和CDFW进行基于模拟的过程比较。为了校准，在L16田口阵列中改变了四种材料和摩擦因素。对不同的仿真质量评价方法进行了评价。通过图像处理确定了镦粗偏差和闪光角α是评价模拟焊缝与实际焊缝对中程度的最合适方法。确定了IFW的最优仿真参数，与实验结果吻合较好。由于摩擦行为依赖于速度和压力，因此不可能将参数直接传递到CDFW，需要进行调整和回归分析才能准确预测。优化后的模拟结果显示了热力学行为的差异：IFW表现出更陡的温度梯度，最小冷却时间为2.5 s，影响区呈双楔状，而CDFW表现出更宽、更均匀的区域，最小冷却时间为3 s。这些发现提高了对IFW和CDFW的理解，并提供了校准的模拟模型，可以促进更有效的工艺开发。

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引用次数: 0

Measurement of residual stress due to deformation caused by slight hydroforming deformation process in double-walled pipes through external pressure 测量外压作用下双壁管中微液压成形变形过程中产生的残余应力

IF 4 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-12-01 Epub Date: 2025-08-05 DOI: 10.1016/j.jajp.2025.100338

Reza Mansourian, Masoud Mahmoodi

In this study, the measurement of residual stress due to deformation caused by slight hydroforming deformation process in double-walled pipes through external pressure was studied. Residual stresses were measured by nanoindentation of ST52 steel/GGG70 iron double-walled pipes. The results showed that the highest compressive residual stress was created on the inner surface of the GGG70 with effective parameters of pressure of 146 tons, the temperature of 73 °C, and percentage of Al₂O₃ nanoparticles powder in fluid of 5.6 %. Repeated nanoindentation measurements on the reference (stress-free) sample showed a variation of approximately 10 %, indicating acceptable repeatability of the method. The stresses are almost uniform and the same along the length of the part, and only very slight changes are observed in the part's initial part. The stress in the outer wall is obtained at the outer surface of ∼ 502.6 MPa and the inner surface of 506.6 MPa. Considering that the yield stress of the outer wall is considered to be ∼ 500 MPa, the entire outer wall is in a plastic state but has undergone a good amount of plastic deformation. Residual stresses are initially tensile and then reach their maximum value and with increasing depth, they are converted into compressive residual stresses and then reach an equilibrium state in the base metal. With increasing depth, there is not much change in the maximum tensile residual stress.

本文研究了外压作用下双壁管材微液压成形过程中变形残余应力的测量。采用纳米压痕法测量了ST52钢/GGG70铁双壁管的残余应力。结果表明：在压力为146 t、温度为73℃、Al₂O₃纳米颗粒粉末在流体中的含量为5.6%的条件下，GGG70的内表面产生的压缩残余应力最大；在参考（无应力）样品上重复的纳米压痕测量显示出大约10%的变化，表明该方法的可重复性是可接受的。应力沿零件的长度几乎是均匀的，只有在零件的初始部分观察到非常微小的变化。外壁应力在外表面为~ 502.6 MPa，内表面为506.6 MPa。考虑外壁屈服应力为~ 500 MPa，整个外壁处于塑性状态，但发生了较好的塑性变形。残余应力最初是拉伸的，然后达到最大值，随着深度的增加，它们转化为压残余应力，然后在母材中达到平衡状态。随着深度的增加，最大拉伸残余应力变化不大。

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引用次数: 0

Microstructure and mechanical properties of ethylene pyrolysis furnace tube weld joints after service 乙烯热解炉管焊缝使用后的组织与力学性能

IF 3.8 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-06-28 DOI: 10.1016/j.jajp.2025.100327

Jingfeng Guo , Xiangping Guo , Xiaoyu Li , Guobing Hu , Wenwen Liu

The microstructure and mechanical properties of weld joints in ethylene pyrolysis furnace (Cr25Ni35NbM alloy and Cr35Ni45NbM alloy tube) after service were investigated in this work. The microstructure of the new weld joint and base metal of pyrolysis furnace tube vary widely, and the high temperature creep rupture time of the weld joint is only reached 50% of the base metal (1100°C, 16MPa). After high-temperature service, the microstructure of weld metal and base metal deteriorated and the high temperature creep strength decreased. Therefore, the microstructure of weld metal and base metal is tend to uniform, and the creep strength of weld joint and base metal reached the same level. After high-temperature aging, the primary carbides coarsen and secondary carbides precipitation results in a uniform microstructure and creep property of weld metal and base metal. The high temperature creep rupture time of weld joint reached 90% of base metal (1100°C, 16MPa). As the dispersion strengthening effect of the secondary carbide disappears, the creep strength of the weld joint no longer increases, but begins to decrease. Both high temperature service and elevated temperature aging result in the homogenization of the weld joint and base metal, and the high-temperature creep strength also reaches the same level.

对乙烯热解炉（Cr25Ni35NbM合金和Cr35Ni45NbM合金管）使用后的焊缝组织和力学性能进行了研究。新型热分解炉管焊缝接头与母材显微组织差异较大，焊缝接头高温蠕变断裂时间仅达到母材的50%（1100℃，16MPa）。高温使用后，焊缝金属和母材组织变质，高温蠕变强度下降。因此，焊缝金属和母材的显微组织趋于均匀，焊缝接头和母材的蠕变强度达到同一水平。高温时效后，初生碳化物粗化，次生碳化物析出，焊缝金属与母材组织和蠕变性能均匀。焊缝高温蠕变断裂时间达到母材的90%（1100℃，16MPa）。随着二次碳化物弥散强化作用的消失，焊缝的蠕变强度不再增加，而是开始降低。高温使用和高温时效均使焊缝与母材均质化，高温蠕变强度达到相同水平。

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引用次数: 0

Application of stress-state-dependent ductile damage and failure model to clinch joining for a wide range of tool and material combinations 应力状态相关的延性损伤和失效模型在各种工具和材料组合的夹持连接中的应用

IF 3.8 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-06-01 Epub Date: 2025-03-24 DOI: 10.1016/j.jajp.2025.100299

Johannes Friedlein , Stephan Lüder , Jan Kalich , Hans Christian Schmale , Max Böhnke , Malte Schlichter , Mathias Bobbert , Gerson Meschut , Paul Steinmann , Julia Mergheim

The clinch joining process is simulated for 22 different tool- and material-combinations, using a modular axisymmetric finite element simulation model. Two ductile metals are considered for the sheets, namely the dual-phase steel HCT590X and the aluminium alloy EN AW-6014 T4. A finite elasto-plastic material model is utilised to capture the inherent large plastic strains. Moreover, it is coupled to stress-state-dependent ductile damage and failure to successfully predict possible fracture during the clinch joining process. For all 22 clinch combinations a good agreement is obtained between simulations and experiments, regarding the geometry of the clinch joint, the process force and the occurrence of material failure. This represents a significant advance in the development and comprehension of a versatile process chain resulting from joint research efforts. The validated process simulations are then applied to study the influence of the tool geometries, sheet pre-stretch, and friction. Failure is herein always observed by neck fracture. Nevertheless, detailed analyses of the stress state evolution during the joining process for various locations reveal that the material is exposed to distinctly non-proportional loading paths demanding suitable stress-state-dependent evolution laws. Moreover, even for valid joints, process-induced damage is distributed throughout the joint. Incorporating the damage-induced softening causes an accelerated failure evolution, but has less influence on the global behaviour.

采用模块化轴对称有限元仿真模型，模拟了22种不同的刀具和材料组合的夹紧连接过程。考虑了两种韧性金属，即双相钢HCT590X和铝合金EN AW-6014 T4。有限弹塑性材料模型用于捕获固有的大塑性应变。此外，它还与应力状态相关的延性损伤和无法成功预测夹接过程中可能发生的断裂相关联。对于所有22种夹紧组合，在夹紧接头的几何形状、工艺力和材料失效的发生方面，模拟结果与实验结果吻合较好。这代表了在开发和理解由联合研究努力产生的通用过程链方面的重大进步。然后应用验证的过程模拟来研究刀具几何形状、板材预拉伸和摩擦的影响。在这里，失败通常以颈部骨折来观察。然而，对不同位置连接过程中应力状态演化的详细分析表明，材料暴露于明显的非比例加载路径，需要合适的应力状态相关演化规律。此外，即使是有效的关节，过程损伤也分布在整个关节中。考虑损伤引起的软化会加速破坏演变，但对整体行为的影响较小。

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引用次数: 0

Optimizing microstructure and performance: The impact of pre-deformation and rotational speed on friction stir processed Cu-W composites 优化组织和性能：预变形和转速对搅拌摩擦加工Cu-W复合材料的影响

IF 3.8 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Journal of Advanced Joining Processes

Pub Date : 2025-06-01 Epub Date: 2025-05-05 DOI: 10.1016/j.jajp.2025.100308

Masoomeh Oliaei, Roohollah Jamaati, Hamed Jamshidi Aval

This study investigated the effects of pre-deformation induced by asymmetric rolling on copper-based metal, as well as rotational speed during friction stir processing, on the microstructure, mechanical properties, and electrical conductivity of tungsten-reinforced copper matrix composites. The results show that increasing the rotational speed up to 800 rpm leads to a more uniform distribution of tungsten particles within the stir zone. However, at rotational speeds above 800 rpm, the distribution of tungsten reinforcing particles becomes less uniform. The accumulated strain in the stir zone increases from 0.3056 to 0.3967 s^-1 as the rotational speed rises from 600 to 1200 rpm. Additionally, as the tool rotational speed increases from 600 to 1200 rpm, the grain size in the stir zone grows from 6.2 ± 0.7 to 13.2 ± 1.5 µm. The Cu-W composite processed at a tool rotational speed of 800 rpm achieves the highest values in hardness (124.9 ± 8.9 HV0.1), ultimate tensile strength (307.4 ± 11.8 MPa), tensile toughness (92.1 ± 1.1 MJ/m³), and electrical conductivity (92.8 ± 1.3 %IACS). Compared to the as-rolled copper-based metal, the electrical conductivity of the Cu-W composite fabricated at 800 rpm increases by 8.8 %.

研究了不对称轧制对铜基金属的预变形以及搅拌摩擦过程中的转速对钨增强铜基复合材料显微组织、力学性能和电导率的影响。结果表明，当转速提高到800 rpm时，搅拌区内钨颗粒的分布更加均匀。然而，当转速超过800转/分时，增强钨颗粒的分布变得不均匀。当转速从600转/分增加到1200转/分时，搅拌区累积应变从0.3056 s-1增加到0.3967 s-1。此外，当刀具转速从600转/分增加到1200转/分时，搅拌区的晶粒尺寸从6.2±0.7µm增加到13.2±1.5µm。当刀具转速为800 rpm时，Cu-W复合材料的硬度（124.9±8.9 HV0.1）、抗拉强度（307.4±11.8 MPa）、抗拉韧性（92.1±1.1 MJ/m3）和电导率（92.8±1.3% IACS）均达到最高值。与轧制时的铜基金属相比，在800转/分下制备的Cu-W复合材料的电导率提高了8.8%。

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引用次数: 0