Materials Science and Engineering: A最新文献_第3页

Enhancement of the mechanical properties of semi-stationary bobbin tool friction stir welded joints in AA2219 through post-weld heat treatment 通过焊后热处理提高 AA2219 半静止线盘工具搅拌摩擦焊接接头的机械性能

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-10 DOI: 10.1016/j.msea.2024.147498

Guilherme N. Rezende , Matteo Bernardi , Marius Hoffmann , Luciano Bergmann , Guilherme Zepon , Benjamin Klusemann

This research investigates the enhancement of AA2219 joints formed by semi-stationary bobbin tool friction stir welding (SSBT-FSW) through post-weld heat treatments. Although solid-state processes such as SSBT-FSW are able to produce superior welds without common defects seen in conventional fusion welding of aluminum alloys of the 2XXX series, the thermal cycle in SSBT-FSW can deteriorate mechanical properties by causing precipitate dissolution and over-aging. The research proposes using a heat treatment sequence to induce solubilization and re-recipitation of precipitates in a more favorable distribution, re-activating the precipitation-hardening. Since abnormal grain growth is very difficult to avoid during heat treatments of welded samples, the analysis focuses on the evolution of the microstructure during solution heat treatment and on the influence of grain size, texture, and precipitate distribution on grain growth. The origin and evolution of the grain growth during solution heat treatment have been observed. Hardness measurements and tensile tests show that post-weld heat treatments can effectively restore the mechanical properties of the joints to the levels of those of the base material. Understanding the relationships between microstructure, abnormal grain growth and mechanical behavior of the joints aids the optimization of the SSBT-FSW process for broader industrial application, especially in the aerospace industry, where high-performance aluminum welded structures are critical.

本研究调查了通过焊后热处理提高半静态线盘工具搅拌摩擦焊（SSBT-FSW）形成的 AA2219 接头的性能。虽然固态工艺（如 SSBT-FSW）能够产生优异的焊缝，不会出现 2XXX 系列铝合金传统熔焊中常见的缺陷，但 SSBT-FSW 的热循环会导致沉淀溶解和过时效，从而降低机械性能。研究建议使用热处理序列来诱导析出物溶解并以更有利的分布重新沉淀，从而重新激活沉淀硬化。由于在焊接样品的热处理过程中很难避免异常晶粒长大，因此分析的重点是固溶热处理过程中微观结构的演变，以及晶粒大小、质地和析出物分布对晶粒长大的影响。我们观察了固溶热处理过程中晶粒生长的起源和演变。硬度测量和拉伸试验表明，焊后热处理可以有效地将接头的机械性能恢复到母材的水平。了解接头的微观结构、异常晶粒长大和机械性能之间的关系有助于优化 SSBT-FSW 工艺，使其应用于更广泛的工业领域，特别是对高性能铝焊接结构至关重要的航空航天工业。

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引用次数: 0

The effect of carbon on the microstructures and mechanical properties of non-equiatomic Cr15Cu5Fe20Mn25Ni35 high-entropy alloy 碳对非等原子 Cr15Cu5Fe20Mn25Ni35 高熵合金微观结构和力学性能的影响

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-09 DOI: 10.1016/j.msea.2024.147525

Majid Vaghari, Kamran Dehghani

This study investigates the effects of carbon addition on the microstructure and mechanical properties of a single-phase face-centered cubic (FCC) Cr₁₅Cu₅Fe₂₀Mn₂₅Ni₃₅ high-entropy alloy (HEA) at room temperature. The alloy was identified as a promising single-phase FCC candidate through systematic thermodynamic calculations using the Calculation of Phase Diagrams (CALPHAD) method and Thermo-Calc software, with validation from X-ray diffraction analysis of the as-cast alloy. The introduction of carbon at concentrations of 0.5 and 1 atomic percent increased the yield strength from 250 MPa to 300 MPa and 350 MPa, respectively, and tensile strength from 500 MPa to 550 MPa and 600 MPa, while enhancing elongation to failure from 20 % to 25 % and 30 %. Microstructural characterization using X-ray diffraction, scanning electron microscopy, and electron backscatter diffraction revealed no alteration in the FCC structure, but a refinement of grain size from 10 μm to 5 μm and a more random crystallographic texture. Additionally, transmission electron microscopy (TEM) analysis demonstrated dense, parallel deformation twins in the alloy with 1 atomic percent of carbon, confirming that twinning significantly contributes to improved ductility and strain hardening. The strengthening effects of carbon are attributed to solid solution strengthening and mechanisms such as twinning. These findings provide valuable insights into tailoring HEA properties through interstitial modifications, contributing to the broader understanding of materials science and the development of high-performance alloys for various applications.

本研究探讨了添加碳对室温下单相面心立方（FCC）Cr15Cu5Fe20Mn25Ni35 高熵合金（HEA）的微观结构和机械性能的影响。通过使用相图计算 (CALPHAD) 方法和 Thermo-Calc 软件进行系统的热力学计算，并通过对铸造合金的 X 射线衍射分析进行验证，确定了该合金是一种有前途的单相 FCC 候选材料。引入浓度为 0.5 和 1 原子百分数的碳后，屈服强度分别从 250 兆帕提高到 300 兆帕和 350 兆帕，抗拉强度从 500 兆帕提高到 550 兆帕和 600 兆帕，而失效伸长率则从 20% 提高到 25% 和 30%。利用 X 射线衍射、扫描电子显微镜和电子反向散射衍射进行的微观结构表征显示，催化裂化结构没有发生变化，但晶粒大小从 10 μm 细化到 5 μm，结晶纹理更加随机。此外，透射电子显微镜（TEM）分析表明，在碳含量为 1 原子百分比的合金中存在致密的平行变形孪晶，证实了孪晶对改善延展性和应变硬化有显著作用。碳的强化作用归因于固溶强化和孪晶等机制。这些发现为通过间隙改性定制 HEA 性能提供了宝贵的见解，有助于更广泛地了解材料科学和开发各种应用的高性能合金。

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引用次数: 0

Corrosion fatigue damage and mechanism evolution of Q420B steel in simulated dry/wet cyclic coastal atmosphere Q420B 钢在模拟干/湿循环沿海大气中的腐蚀疲劳损伤和机理演变

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-09 DOI: 10.1016/j.msea.2024.147515

Hongqiang Chu , Yanjin Guan , Jiqiang Zhai , Fengjiao Chen , Jun Lin

Q420B low-alloy high-strength steel is the primary material used in China's ultra-high voltage (UHV) transmission towers. In coastal regions, the interaction of wind-induced fatigue and atmospheric corrosion makes it vulnerable to corrosion fatigue (CF), endangering grid safety. This study investigates the CF behavior and underlying mechanisms of Q420B steel, utilizing a specially designed dry/wet cyclic CF device. The results indicate that Q420B steel exhibits high sensitivity to CF, with the failure mechanism being controlled by anodic dissolution and hydrogen embrittlement. The crack initiation process unfolds in three stages: the formation of surface corrosion products, pitting corrosion beneath the rust layer, and nucleation of corrosion fatigue cracks (CFCs). Under low peak stress, anodic dissolution, hydrogen diffusion, and plastic deformation at the crack tip collectively hasten the propagation of CFCs. Under high peak stress, the mechanical effect at the crack tip dominates CFCs propagation. These insights are vital for optimizing the design and maintenance of UHV transmission towers.

Q420B 低合金高强度钢是中国特高压输电塔的主要材料。在沿海地区，风引起的疲劳和大气腐蚀的相互作用使其容易发生腐蚀疲劳（CF），危及电网安全。本研究利用专门设计的干/湿循环 CF 设备，对 Q420B 钢的 CF 行为和基本机制进行了研究。结果表明，Q420B 钢对腐蚀疲劳具有高度敏感性，其失效机理受阳极溶解和氢脆控制。裂纹萌发过程分为三个阶段：表面腐蚀产物的形成、锈层下的点蚀和腐蚀疲劳裂纹（CFCs）的成核。在低峰值应力下，阳极溶解、氢扩散和裂纹尖端的塑性变形共同加速了 CFC 的扩展。在峰值应力较高的情况下，裂纹尖端的机械效应会主导 CFCs 的扩展。这些见解对于优化超高压输电塔的设计和维护至关重要。

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引用次数: 0

High-temperature compressive behaviour and failure mechanism of high entropy carbides modified by Cr addition 添加铬改性的高熵碳化物的高温压缩行为和失效机理

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-09 DOI: 10.1016/j.msea.2024.147532

Yichen Wang , Zanlin Cheng , Vladimír Girman , Richard Sedlák , Ján Dusza , Michael J. Reece , Chengyu Zhang

The effect of Cr addition on the compressive and failure behaviour of high entropy carbides (HECs) at temperatures of 1400–1600 °C and stresses of 200–300 MPa was investigated by comparing two groups of ceramics: (Zr,Nb,Hf,Ta)C (HEC4) and HEC4 with Cr addition (HEC5-Cr), and 8-metal carbides (Ti,Zr,Hf,V,Nb,Ta,Mo,X)C with W or Cr addition for X. The HEC-Cr systems showed significantly lower compressive strain than Cr-free HECs under identical conditions. HEC4 showed a strain of about 1.4 % at 1500 °C under 200 MPa for 6 h, while HEC5-Cr demonstrated only 0.05 % strain. To the best of our knowledge, HEC5-Cr exhibited the lowest steady creep rate among carbides reported under similar conditions. Creep is almost negligible in HEC-Cr ceramics, mostly because the grain boundary sliding and cracking were restricted by the strong Cr-rich grain boundaries. The Cr addition changed the failure behaviour of HECs: the Cr-free HEC samples shattered into numerous pieces due to severe grain boundary deformation, the HEC-Cr samples typically fractured into two parts with transgranular failure. The strategic addition of Cr to HECs enhances compressive performance and modifies fracture behaviour, indicating their potential as superior materials for high-stress, high-temperature applications.

通过比较两组陶瓷：(Zr,Nb,Hf,Ta)C (HEC4)和添加了铬的 HEC4 (HEC5-Cr)，以及添加了 W 或铬的 X 的 8 金属碳化物 (Ti,Zr,Hf,V,Nb,Ta,Mo,X)C，研究了添加铬对高熵碳化物 (HEC) 在 1400-1600 °C 温度和 200-300 MPa 应力条件下的压缩和破坏行为的影响。在相同条件下，HEC-Cr 系统的压缩应变明显低于无铬 HEC。HEC4 在 1500 °C、200 兆帕持续 6 小时的条件下显示出约 1.4 % 的应变，而 HEC5-Cr 仅显示出 0.05 % 的应变。据我们所知，HEC5-Cr 在类似条件下表现出的稳定蠕变率是所报道的碳化物中最低的。HEC-Cr 陶瓷的蠕变几乎可以忽略不计，这主要是因为晶界滑动和开裂受到了富含铬的强晶界的限制。铬的添加改变了 HEC 的破坏行为：无铬 HEC 样品由于严重的晶界变形而碎裂成许多碎片，而 HEC-Cr 样品通常断裂成两部分，发生跨晶粒破坏。有策略地在 HEC 中添加铬可提高抗压性能并改变断裂行为，这表明 HEC 有可能成为高应力、高温应用领域的优质材料。

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引用次数: 0

Additive manufacturing Cr-Mo-Si-V steel: Systematic parameter assessments, precipitation behavior of in-situ VC-M23C6 and strengthening mechanisms 铬-钼-硅-钒钢的快速成型制造：系统参数评估、原位 VC-M23C6 的析出行为和强化机制

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-09 DOI: 10.1016/j.msea.2024.147504

Qing Wang , Deyin Kong , Xingran Li , Shihui Zhou , Zhihui Zhang

To obtain the H13 steel with defect-structure-performance compatibility fabricated by laser powder bed fusion (LPBF), a systematic optimisation framework was employed to get optimal process window in this paper. Subsequently, the microstructural evolutions, nanoprecipitation behaviors and strengthening mechanisms of H13 steels built at recommended parameters were in-depth analyzed. The evolutions of submicron sized cellular and columnar dendritic crystal were explained as well as the phase transformation process including lath martensite with a twin substructure and the carbon-rich residual austenite (RA) films were revealed. Two nano carbides, MC (rich in V and Mo) as well as M₂₃C₆ (rich in Cr and Mn), with diameters of 10–40 nm, were precipitated due to the intrinsic heat treatment (IHT) in LPBF process. Cr₂₃C₆ particles preferentially nucleated at the grain and subgrain boundaries due to the presence of crystalline defects such as dislocations and stacking faults caused by lattice distortion. It then grew by alloying elemental depletion while remaining semi-coherency with the α-Fe matrix. VC particles nucleated in situ within M₂₃C₆ as V atoms accumulated and replaced M atoms in the M₂₃C₆ lattice. With the growth of VC nuclei, the strain energy caused by local lattice misfit increased. This was offset by the development of self-accommodating twins featuring a long-period stacking order substructure within the VC particles. Eventually, spheroidal VC with twin structure were embedded in or adjacent to M₂₃C₆ carbides, and the orientation relationships for VC/M₂₃C₆ and VC/α-Fe were revealed. The as-built H13 steel exhibited excellent hardness and strength compared to wrought H13 steel, which was mainly attributed to dislocation strengthening and grain boundary strengthening, with precipitation strengthening playing a secondary role due to the low amount of nanoprecipitates. The low elongation (El) at fracture was closely related to the instability of RA films as well as the residual stress.

为了通过激光粉末床熔融（LPBF）获得具有缺陷-结构-性能兼容性的 H13 钢，本文采用了系统优化框架来获得最佳工艺窗口。随后，深入分析了在推荐参数下制造的 H13 钢的微观结构演变、纳米沉淀行为和强化机制。本文解释了亚微米级蜂窝状和柱状树枝状晶体的演变过程，并揭示了包括具有孪生亚结构的板条马氏体和富碳残余奥氏体（RA）膜在内的相变过程。由于 LPBF 工艺中的固有热处理（IHT），析出了直径为 10-40 纳米的两种纳米碳化物 MC（富含 V 和 Mo）以及 M23C6（富含 Cr 和 Mn）。由于晶格畸变引起的位错和堆积断层等晶体缺陷的存在，Cr23C6 颗粒优先在晶粒和亚晶粒边界成核。然后，在与α-铁基体保持半相干性的同时，通过合金元素贫化而生长。随着 V 原子在 M23C6 晶格中累积并取代 M 原子，VC 粒子在 M23C6 中就地成核。随着 VC 核的增长，由局部晶格错配引起的应变能也随之增加。但这一现象被 VC 粒子内具有长周期堆积阶次结构的自适应孪晶的发展所抵消。最终，具有孪晶结构的球状 VC 被嵌入 M23C6 碳化物中或与之相邻，并揭示了 VC/M23C6 和 VC/α-Fe 的取向关系。与锻造 H13 钢相比，坯钢具有优异的硬度和强度，这主要归因于位错强化和晶界强化，由于纳米沉淀物含量较低，沉淀强化起次要作用。断裂伸长率（El）较低与 RA 膜的不稳定性和残余应力密切相关。

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引用次数: 0

Dynamic deformation behaviors and structure evolution of TiZrHf hexagonal closed-packed medium-entropy alloy TiZrHf 六方封闭堆积中熵合金的动态变形行为和结构演化

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-09 DOI: 10.1016/j.msea.2024.147516

Zhenhua Han , Yubo Tian , Jun Yang , Yanchang Liu , Gang Liu , Zilu Wang , Ran Wei , Guojun Zhang , Hongyan Wang

In this study, the deformation behavior of a hexagonal closed-packed (HCP) TiZrHf medium-entropy alloy (MEA) was investigated across a wide range of strain rates from 10⁻⁴ s⁻¹ to 4990 s⁻¹. The alloy exhibits an exceptional combination of strength and plasticity during dynamic loading, as well as a noticeable strain rate hardening effect. The strain rate hardening effect is associated with the strong dislocation drag resulting from the fast dislocation velocity at high strain rates. Microstructure evolution analyses demonstrate that various deformation mechanisms occur within shear bands under dynamic loading, including the formation of deformation twins, dislocation cells, microbands, amorphous bands, and dynamic recrystallization. The dynamic deformation is influenced by the competition between hardening mechanisms and thermal softening effects. Dislocations, deformation twins, and amorphous bands dominate the strain hardening effect, while temperature rise induced by adiabatic shear contributes to thermal softening effects. Additionally, dynamic recrystallization and amorphization also lead to a decrease in dislocation density during dynamic loading.

本研究调查了六方封闭堆积（HCP）TiZrHf 中熵合金（MEA）在 10-4 s-1 至 4990 s-1 宽应变速率范围内的变形行为。该合金在动态加载过程中表现出优异的强度和塑性组合，以及明显的应变速率硬化效应。应变速率硬化效应与高应变速率下快速位错速度产生的强位错阻力有关。微观结构演变分析表明，在动态加载条件下，剪切带内部会发生各种变形机制，包括形成变形孪晶、位错单元、微带、非晶带和动态再结晶。动态变形受硬化机制和热软化效应之间竞争的影响。位错、变形孪晶和非晶带在应变硬化效应中占主导地位，而绝热剪切引起的温度升高则有助于热软化效应。此外，在动态加载过程中，动态再结晶和非晶化也会导致位错密度下降。

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引用次数: 0

Enhancing tensile and creep properties of Inconel 617 superalloy via regulating the synergistic evolution of M23C6 carbides and γ′ phases 通过调节 M23C6 碳化物和 γ′ 相的协同演化提高 Inconel 617 超耐热合金的拉伸和蠕变性能

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-08 DOI: 10.1016/j.msea.2024.147523

Zhiyang Zhang, Ran Ding, Qianying Guo, Chenxi Liu, Yongchang Liu

A novel heat treatment strategy, termed solution-double aging treatment (SDAT), is proposed to enhance the tensile properties and creep resistance at high-temperature of Inconel 617 Ni-based superalloy. This method aims to achieve a microstructure that maintains excellent thermal stability at elevated temperature up to 760 °C. The results suggest that the improved tensile properties of SDAT-treated alloys are attributable to orderly precipitation and synergistic interaction of M₂₃C₆ carbides and γ′ phases. Under identical creep conditions, SDAT alloys significantly enhance creep strength and extend creep rupture life in comparison to solution-treated (ST) alloys. Specifically, under creep conditions of 760 °C/170 MPa, SDAT alloys exhibit a 37.25 % longer creep rupture life than ST alloys, particularly under low-stress conditions. The enhanced creep properties of SDAT alloys are due to the unique microstructure produced by the SDAT treatment: the high-density and small-size of γ′ phases effectively impede dislocation movement, thereby reducing the minimum creep rate; the evolution of cylindrical coarse M₂₃C₆ carbides predominantly occurs near grain boundaries or within grains, reducing the formation of creep cracks; the high proportion of grain boundary M₂₃C₆ carbides mitigates creep damage caused by carbide evolution, inhibiting the initiation and extension of grain boundary cracks. The SDAT heat treatment process provides a novel approach to improving the creep life of Ni-based superalloys by controlling the synergistic evolution mechanisms of carbides and γ′ phases.

为提高 Inconel 617 镍基超合金在高温下的拉伸性能和抗蠕变性，提出了一种新的热处理策略，即固溶-双时效处理（SDAT）。这种方法的目的是获得一种在高达 760 °C 的高温下仍能保持优异热稳定性的微观结构。研究结果表明，SDAT 处理合金拉伸性能的改善归因于 M23C6 碳化物和 γ′ 相的有序析出和协同作用。在相同的蠕变条件下，与溶液处理（ST）合金相比，SDAT 合金能显著提高蠕变强度并延长蠕变断裂寿命。具体来说，在 760 °C/170 兆帕的蠕变条件下，SDAT 合金的蠕变断裂寿命比 ST 合金长 37.25%，尤其是在低应力条件下。SDAT 合金蠕变性能的增强得益于 SDAT 处理所产生的独特微观结构：高密度和小尺寸的 γ′ 相有效地阻碍了位错运动，从而降低了最小蠕变速率；圆柱形粗大 M23C6 碳化物的演化主要发生在晶界附近或晶粒内部，减少了蠕变裂纹的形成；高比例的晶界 M23C6 碳化物减轻了碳化物演化造成的蠕变损伤，抑制了晶界裂纹的产生和扩展。通过控制碳化物和γ′相的协同演化机制，SDAT热处理工艺为提高镍基超合金的蠕变寿命提供了一种新方法。

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引用次数: 0

On the dynamic failure mechanism of Vit-1 bulk metallic glass: Coupling effects of pre-made damage and strain rate Vit-1 块状金属玻璃的动态破坏机理：预制损伤和应变速率的耦合效应

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-08 DOI: 10.1016/j.msea.2024.147522

Yang Han , Zejian Xu , P.J. Tan , Mengyu Su , Jianfei Li , Fenglei Huang

To clarify the two distinct effects and the underlying physical mechanisms of pre-made damage on the failure strength of bulk metallic glass (BMG), i.e. strengthening or weakening, the influence of axial pre-compression on the dynamic failure of Vit-1 BMG are investigated experimentally. Quasi-static and dynamic compression tests were conducted on pre-compressed BMG specimens for a wide range of nominal strain rates between 0.001 s⁻¹ to 6000 s⁻¹. The focus is on the coupled effects of pre-compression and strain rate on the dynamic failure stress. Two contrasting mechanisms were identified that influence how the pre-made shear bands affect the propagation of cracks under different strain rates. It will be shown that the dynamic failure stress exhibits a transition from strengthening to knockdown with increasing strain rate; and, that the extent of these strengthening and knockdown effects depends on the pre-compression strain level. Finally, a failure model that captures the effects of both strain rate and pre-made damage is proposed.

为了阐明预制损伤对块状金属玻璃（BMG）失效强度的两种不同影响及其基本物理机制，即增强还是削弱，我们通过实验研究了轴向预压缩对 Vit-1 BMG 动态失效的影响。在 0.001 s-1 至 6000 s-1 的宽标称应变率范围内，对预压 BMG 试样进行了准静态和动态压缩试验。重点是预压缩和应变率对动态破坏应力的耦合效应。研究发现了两种截然不同的机制，它们影响着预制剪切带在不同应变速率下对裂纹扩展的影响。结果表明，随着应变速率的增加，动态破坏应力会从增强过渡到减弱；而且这些增强和减弱效应的程度取决于预压缩应变水平。最后，我们将提出一个能同时捕捉应变率和预制损伤效应的失效模型。

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引用次数: 0

A comprehensive overview of additive manufacturing aluminum alloys: Classifications, structures, properties and defects elimination 全面介绍快速成型制造铝合金：分类、结构、性能和缺陷消除

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-08 DOI: 10.1016/j.msea.2024.147464

Xianwen Yang , Ruidi Li , Tiechui Yuan , Linda Ke , Jie Bai , Kai Yang

Aluminum alloys, known for their high strength, good toughness, and lightweight properties, are widely used in aerospace, rail transportation, and other fields. 3D printing, as an emerging additive manufacturing (AM) technology, achieves the transformation from digital models to physical products through layer-by-layer material deposition. This processing method significantly enhances the flexibility of both design and manufacturing, while also enabling the efficient production of complex piping and intricate cavity structures. This paper comprehensively and systematically introduces the classification, structure, performance, defects, and elimination methods of AM aluminum alloys. It begins with an introduction to AM technologies and traditional aluminum alloys. Then, it discusses the classifications and performances of AM aluminum alloys, such as Al-Si, Al-Mg-(Sc, Zr), Al-Cu-(Mg), Al-Zn-Mg-(Cu), Al-Fe, Al-Ni, Al-Mn, and Al-based composites, and providing a detailed and comprehensive overview of the mechanical properties (both in horizontal and vertical directions), heat resistance, fatigue performance, creep behavior, corrosion resistance, impact resistance, and wear resistance of the alloys. It also discusses the potential defects of different types of alloys and their mitigation methods, especially the formation mechanisms and elimination methods of porosity, deformation, and cracking. Moreover, the role of refiners in 3D-printed aluminum alloys is separately demonstrated. Finally, the paper presents the practical applications and prospects of 3D printed aluminum alloys, aiming to establish a systematic and comprehensive framework to provide a multi-faceted overview of aluminum alloys in AM, offering valuable insights and guidance for scientific research and industrial applications.

铝合金以其强度高、韧性好、重量轻等特性著称，被广泛应用于航空航天、轨道交通等领域。三维打印作为一种新兴的增材制造（AM）技术，通过逐层材料沉积实现了从数字模型到实体产品的转变。这种加工方法大大提高了设计和制造的灵活性，同时还能高效生产复杂的管道和复杂的空腔结构。本文全面系统地介绍了 AM 铝合金的分类、结构、性能、缺陷和消除方法。本文首先介绍了 AM 技术和传统铝合金。然后，讨论了 AM 铝合金的分类和性能，如 Al-Si、Al-Mg-(Sc, Zr)、Al-Cu-(Mg)、Al-Zn-Mg-(Cu)、Al-Fe、Al-Ni、Al-Mn 和铝基复合材料，并详细、全面地概述了这些合金的机械性能（水平方向和垂直方向）、耐热性、疲劳性能、蠕变行为、耐腐蚀性、耐冲击性和耐磨性。报告还讨论了不同类型合金的潜在缺陷及其缓解方法，特别是气孔、变形和裂纹的形成机制和消除方法。此外，还分别论证了精炼剂在 3D 打印铝合金中的作用。最后，论文介绍了 3D 打印铝合金的实际应用和前景，旨在建立一个系统而全面的框架，对 AM 中的铝合金进行多方面的概述，为科学研究和工业应用提供有价值的见解和指导。

{"title":"A comprehensive overview of additive manufacturing aluminum alloys: Classifications, structures, properties and defects elimination","authors":"Xianwen Yang , Ruidi Li , Tiechui Yuan , Linda Ke , Jie Bai , Kai Yang","doi":"10.1016/j.msea.2024.147464","DOIUrl":"10.1016/j.msea.2024.147464","url":null,"abstract":"<div><div>Aluminum alloys, known for their high strength, good toughness, and lightweight properties, are widely used in aerospace, rail transportation, and other fields. 3D printing, as an emerging additive manufacturing (AM) technology, achieves the transformation from digital models to physical products through layer-by-layer material deposition. This processing method significantly enhances the flexibility of both design and manufacturing, while also enabling the efficient production of complex piping and intricate cavity structures. This paper comprehensively and systematically introduces the classification, structure, performance, defects, and elimination methods of AM aluminum alloys. It begins with an introduction to AM technologies and traditional aluminum alloys. Then, it discusses the classifications and performances of AM aluminum alloys, such as Al-Si, Al-Mg-(Sc, Zr), Al-Cu-(Mg), Al-Zn-Mg-(Cu), Al-Fe, Al-Ni, Al-Mn, and Al-based composites, and providing a detailed and comprehensive overview of the mechanical properties (both in horizontal and vertical directions), heat resistance, fatigue performance, creep behavior, corrosion resistance, impact resistance, and wear resistance of the alloys. It also discusses the potential defects of different types of alloys and their mitigation methods, especially the formation mechanisms and elimination methods of porosity, deformation, and cracking. Moreover, the role of refiners in 3D-printed aluminum alloys is separately demonstrated. Finally, the paper presents the practical applications and prospects of 3D printed aluminum alloys, aiming to establish a systematic and comprehensive framework to provide a multi-faceted overview of aluminum alloys in AM, offering valuable insights and guidance for scientific research and industrial applications.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"919 ","pages":"Article 147464"},"PeriodicalIF":6.1,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656759","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

Achieving high strength and low yield ratio by constructing the network martensite-ferrite heterogeneous in low carbon steels 通过在低碳钢中构建马氏体-铁素体异质网络实现高强度和低屈强比

IF 6.1 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2024-11-08 DOI: 10.1016/j.msea.2024.147526

Xiong Du , Liexing Zhou , Jun Li , Zhenwei Xie , Shaohong Li , Hongbo Xiao , Mengnie Li , Yuanjie Zhao

In this research, focusing on low-carbon steel, a martensite-ferrite heterogeneous structure dual-phase (MFDP) steel with a network morphology where ferrite is surrounded by martensite was obtained via cyclic annealing and subcritical quenching heat treatment processes. With the initial microstructure of ferrite and lamellar pearlite, a spherical pearlite and martensitic structure surrounding the ferrite was first obtained by applying the cyclic annealing process near the Ac₁ temperature. Subsequently, the annealed structure was subjected to subcritical quenching heat treatment, thereby establishing a network-like martensite-ferrite dual-phase heterogeneous structure and named N-760 °C and N-780 °C. In comparison with the ferrite-martensite dual-phase steel where ferrite envelopes martensite, N-780 °C witnessed a marked increase in tensile strength and uniform elongation, while the yield ratio dropped by 20 %. Through cyclic loading and unloading tensile tests, it was found that the N-760 °C showed a more obvious heterogeneous deformation-induced (HDI) strengthening effect. The results from electron backscattering and transmission electron microscopy indicate that, in the N-760 °C, a small quantity of dislocations is produced in the ferrite due to the martensitic phase transformation prior to the tensile test. During the tensile process, as the strain increases, the ferrite undergoes significant deformation, and the intragranular dislocations re-arrange to form dislocation cells and deformation-induced grain boundaries (SIBs). Meanwhile, geometrically necessary dislocations (GNDs) accumulate at the ferrite/martensite interface. Therefore, the non-coordinated deformation between the mesh-like dual-phase microstructure offers additional HDI strengthening for MFDP steel.

本研究以低碳钢为研究对象，通过循环退火和亚临界淬火热处理工艺，获得了一种马氏体-铁素体异质结构双相钢（MFDP），这种钢具有铁素体被马氏体包围的网络形态。初始微观结构为铁素体和片状珠光体，通过在 Ac1 温度附近进行循环退火工艺，首先获得了环绕铁素体的球状珠光体和马氏体结构。随后，对退火结构进行亚临界淬火热处理，从而建立起网络状的马氏体-铁素体双相异质结构，并命名为 N-760 ℃ 和 N-780 ℃。与铁素体包裹马氏体的铁素体-马氏体双相钢相比，N-780 ℃的抗拉强度和均匀伸长率显著提高，而屈强比下降了20%。通过循环加载和卸载拉伸试验发现，N-760 °C表现出更明显的异质变形诱导（HDI）强化效果。电子反向散射和透射电子显微镜的结果表明，在 N-760 ℃ 拉伸试验之前，由于马氏体相变，铁素体中产生了少量位错。在拉伸过程中，随着应变的增加，铁素体发生显著变形，晶内位错重新排列，形成位错单元和变形诱导晶界（SIB）。与此同时，几何必要位错（GNDs）在铁素体/马氏体界面上聚集。因此，网状双相微结构之间的非协调变形为 MFDP 钢提供了额外的 HDI 强化。

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引用次数: 0