Materials Science and Engineering: A最新文献

Mechanical properties and strengthening–toughening mechanisms of the TC21 titanium alloy with different microstructures 不同组织TC21钛合金的力学性能及增韧机理

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-26 DOI: 10.1016/j.msea.2026.150156

Yang Xiang , Wei Xiang , Qiang Fu , Wuhua Yuan

This study developed TC21 titanium alloy (TA) forgings with three microstructures (bimodal [BM], lamellar [LM], and basket-weave [BW]) through forging and heat treatment. Their comprehensive mechanical properties were evaluated via room-temperature tensile, fracture toughness, and impact toughness tests. Microstructural analysis was conducted using super-depth-of-field microscopy, scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy, and laser scanning confocal microscopy to characterize the microstructure, fracture morphology, and crack propagation paths. The mechanical properties of the three samples were compared, and their strengthening and toughening mechanisms were investigated. Results indicated that the main strengthening phase in TC21 was the fine secondary α_S phase within the transformed β structure, which led to considerable strengthening through second-phase strengthening. The main toughening phase was coarse α laths (α_L), which enhanced toughness by increasing the crack propagation path length and energy consumption per unit crack length. In the BM microstructure, the equiaxed primary α_P phase exhibited excellent plastic deformation capability, providing larger slip space for dislocations and coordinating deformation through grain rotation. In the LM microstructure, slip systems propagated through numerous parallel α_L and β phases. The effective slip space for dislocations was measured within α colonies, which indicated enhanced plasticity. The BW microstructure exhibited optimal comprehensive mechanical properties, including a tensile strength of 1123 MPa, an elongation of 10.4%, a fracture toughness of 96.0 MPa·m^1/2, and an impact toughness of 42.4 J/cm².

通过锻造和热处理，研制出具有双峰[BM]、片层[LM]和篮织[BW]三种显微组织的TC21钛合金（TA）锻件。通过室温拉伸、断裂韧性和冲击韧性试验对其综合力学性能进行了评价。采用超景深显微镜、扫描电镜、电子背散射衍射、透射电镜、激光扫描共聚焦显微镜等进行显微组织分析，表征材料的显微组织、断口形貌和裂纹扩展路径。比较了三种试样的力学性能，并对其强化增韧机理进行了探讨。结果表明：TC21的主要强化相是转变后的β组织内细小的次级αS相，通过第二相强化获得了较大的强化效果；粗α条（α l）为主要增韧相，通过增加裂纹扩展路径长度和单位裂纹长度能量消耗来增强韧性。在BM组织中，等轴初生αP相表现出优异的塑性变形能力，为位错提供了较大的滑移空间，并通过晶粒旋转协调变形。在LM微观结构中，滑移体系通过大量平行的αL相和β相传播。在α菌落内测量了位错的有效滑移空间，表明塑性增强。拉伸强度为1123 MPa，延伸率为10.4%，断裂韧性为96.0 MPa·m1/2，冲击韧性为42.4 J/cm2，综合力学性能最佳。

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引用次数: 0

Tensile and creep properties of casting high Nb-TiAl alloy studied by hot isostatic pressing 用热等静压法研究了铸造高Nb-TiAl合金的拉伸和蠕变性能

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-02-06 DOI: 10.1016/j.msea.2026.149900

Jun Cao , Shuangzan Wang , Jiabin Zuo , Xianfei Ding , Wen Yu , Zhichao Guo , Yongfeng Liang , Junpin Lin

Hot isostatic pressing (HIP) is an effective way to adjust the microstructure and mechanical properties of alloys, and is a commonly used hot working process. However, few studies have been conducted on the use of HIP for adjusting casting high Nb-TiAl alloys. In this paper, the effects of HIP on the tensile properties and creep properties of Ti-46Al-5Nb-0.1C alloy at room temperature (RT) and 800 °C were investigated by analyzing the microstructure characteristics, tensile and creep fracture morphology, and creep microstructure of as-cast and HIPed alloys. The results show that HIP significantly improves the RT ductility of the alloy up to 1.3% and maintains a high tensile strength. This is attributed to the elimination of casting defects such as shrinkage cavities, the increase of γ phase content, and the obtained duplex microstructure with equiaxed γ grains distributed among lamellar colonies. HIP significantly changed the creep behavior of the alloy. Numerous deformation twins were observed in the creep microstructure of HIP alloys. Creep fracture appears dimples. Plasticity characteristics are obvious. The creep life and elongation of HIPed alloy become longer. With increased plasticity, HIPed alloys occupy 81% of the creep life during the accelerated creep stage. The Ti-46Al-5Nb-0.1C alloy treated by HIP has better mechanical properties and creep life at the service temperature.

热等静压是一种有效调节合金组织和力学性能的方法，是一种常用的热加工工艺。然而，利用HIP调节铸造高Nb-TiAl合金的研究很少。本文通过分析铸态和HIPed合金的显微组织特征、拉伸和蠕变断口形貌以及蠕变组织，研究了HIP对Ti-46Al-5Nb-0.1C合金室温和800℃拉伸和蠕变性能的影响。结果表明，HIP处理可使合金的塑性提高1.3%，并保持较高的抗拉强度。这是由于消除了缩孔等铸造缺陷，增加了γ相含量，获得了等轴γ晶粒分布在片层集落中的双相组织。HIP显著改变了合金的蠕变行为。在HIP合金蠕变组织中观察到大量变形孪晶。蠕变断口出现韧窝。塑性特性明显。HIPed合金的蠕变寿命和伸长率提高。随着塑性的增加，加速蠕变阶段的蠕变寿命占合金蠕变寿命的81%。经HIP处理的Ti-46Al-5Nb-0.1C合金在使用温度下具有较好的力学性能和蠕变寿命。

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引用次数: 0

Short-time annealing achieves interfacial equilibration and strength-ductility synergy in ultrasonic additive manufactured Ti/Al laminated composites 在超声添加剂制备的Ti/Al层合复合材料中，短时间退火实现了界面平衡和强度-延性协同

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-02-05 DOI: 10.1016/j.msea.2026.149891

Yanyuan Zhou , Hu Zong , Xianmeng Tu , Tongfang Wang , Su Zhao

Ultrasonic additive manufacturing (UAM) was employed to fabricate Ti/Al laminated composites and elucidate the relationship between interfacial microstructure and macroscopic tensile behavior. The UAM process produced thermally asymmetric interfaces, where the Ti/Al interface experienced higher local temperatures and more intense plastic deformation, promoting partial dynamic recrystallization and Al grain refinement. In contrast, the Al/Ti interface underwent limited recovery and retained a softer structure. Digital image correlation (DIC) mapping revealed pronounced strain partitioning, with shear localization concentrated near the recrystallized Ti/Al interface. Subsequent short-time annealing induced grain coarsening, dislocation recovery, and stress relaxation at both interfaces, reducing hardness mismatch and improving strain compatibility. The heat-treated laminates exhibited smoother strain fields, more uniform deformation, and a simultaneous enhancement in strength and ductility. Correlative EBSD, TEM, and DIC analyses established a clear mechanistic link between interfacial microstructural evolution and macroscopic deformation response. The findings demonstrate that achieving an optimal strength-ductility synergy in UAM Ti/Al laminates relies primarily on regulating interfacial recrystallization and residual stress rather than merely strengthening the metallurgical bond.

采用超声增材制造技术制备了Ti/Al层合复合材料，研究了界面微观结构与宏观拉伸性能的关系。UAM工艺产生了热不对称界面，其中Ti/Al界面经历了更高的局部温度和更强烈的塑性变形，促进了部分动态再结晶和Al晶粒细化。相比之下，Al/Ti界面恢复有限，保留了较软的结构。数字图像相关（DIC）映射显示出明显的应变分配，剪切局部化集中在再结晶Ti/Al界面附近。随后的短时间退火诱导了两个界面的晶粒粗化、位错恢复和应力松弛，减少了硬度错配，提高了应变相容性。热处理后的层压板表现出更平滑的应变场，更均匀的变形，同时增强了强度和延展性。相关的EBSD、TEM和DIC分析明确了界面微观结构演化与宏观变形响应之间的机制联系。研究结果表明，在UAM Ti/Al层压板中实现最佳的强度-塑性协同作用主要依赖于调节界面再结晶和残余应力，而不仅仅是加强冶金结合。

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引用次数: 0

Microstructure evolution during solution treatment and its effect on the tensile properties at 700 °C of a novel near-α high temperature titanium alloy 一种新型近α高温钛合金固溶过程中的组织演变及其对700℃拉伸性能的影响

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-02-07 DOI: 10.1016/j.msea.2026.149898

Bin Yao , Zhenhua Han , Yanchang Liu , Mengyao Li , Qingqing Gong , Xiaoyu Fan , Ran Wei

To achieve a synergistic combination of high strength and ductility in titanium alloys at 700 °C, a novel near-α high temperature titanium alloy Ti–5.8Al–4.0Sn–4.0Zr–0.31Nb–0.62Ta–1.26W–0.4Si was designed. The microstructure was subsequently optimized through hot forging followed by heat treatment, and its microstructural evolution was systematically investigated. Results indicated that with increasing solution temperature from 950 °C to 1050 °C, the volume fraction of primary equiaxed α phase (α_p) decreased while the transformed β phase (β_t) and secondary lamellar α phase (α_s) increased. The microstructure evolved from predominantly equiaxed α to a lamellar structure. Tensile tests conducted at 700 °C revealed that the samples solution-treated in the upper half of the α+β region (1000 °C) exhibited the superior combination of strength and ductility, achieving a tensile strength of 576.2 MPa while maintaining an elongation of 22.3%. The superior mechanical properties can be attributed to the refined α_p and β_t phases. The dislocation motion is hindered by fine α_s lamellae while interfacial pinning effects combined with an oriented arrangement of dispersed S₂ silicide precipitates contribute to synergistic strengthening.

为使钛合金在700℃时实现高强度和高塑性的协同结合，设计了一种新型近α高温钛合金Ti-5.8Al-4.0Sn-4.0Zr-0.31Nb-0.62Ta-1.26W-0.4Si。通过热锻再热处理优化其组织，系统研究其组织演变规律。结果表明：从950℃到1050℃，随着溶液温度的升高，初生等轴α相（αp）的体积分数降低，转变β相（βt）和次生片层α相（αs）的体积分数增加；显微组织由主要的等轴α演变为片层结构。在700℃下进行的拉伸试验表明，在α+β区上半部分（1000℃）固溶处理的样品具有较好的强度和延展性，抗拉强度达到576.2 MPa，伸长率为22.3%。αp和βt相的细化使其具有优异的力学性能。细小的αs片层阻碍了位错的运动，而界面钉钉效应和分散的S2硅化物沉淀的定向排列有助于协同强化。

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引用次数: 0

Decoupling the elemental contributions of Al to the creep behavior of high-temperature titanium alloys 解耦了Al元素对高温钛合金蠕变行为的影响

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-02-12 DOI: 10.1016/j.msea.2026.149919

Zhuomeng Liu , Shewei Xin , Yongqing Zhao

Using single-phase Ti-6Al as a model system, we show that creep transitions from Al-solute-diffusion-controlled viscous glide at low temperatures/stresses to Ti-lattice-diffusion-controlled dislocation climb at higher conditions. At 550 °C/250 MPa, creep entered a damage-controlled tertiary instability regime, and the power-law relationship broke down, providing mechanistic guidance for designing high-temperature titanium alloys.

使用单相Ti-6Al作为模型系统，我们发现蠕变从低温/应力下的al -溶质扩散控制的粘滑转变为较高条件下的ti -晶格扩散控制的位错爬升。550℃/250 MPa时，蠕变进入损伤控制的三级失稳状态，幂律关系失效，为高温钛合金的设计提供了机理指导。

引用次数: 0

Microstructure evolution in additively manufactured Ti-15%Nb-12%Zr alloy during plastic deformation over a wide range of strain up to 20,800 % 增材制造Ti-15%Nb-12%Zr合金在20,800 %应变范围内塑性变形过程中的组织演变

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-01-27 DOI: 10.1016/j.msea.2026.149842

Kamilla Mukhtarova , Guy Dirras , Megumi Kawasaki , Csilla Kádár , Márk Windisch , Anita Heczel , Zoltán Dankházi , György Zoltán Radnóczi , Jenő Gubicza

The evolution of the microstructure during plastic deformation was studied in an additively manufactured Ti-15%Nb-12%Zr (at.%) alloy. The applied equivalent strain ranged extremely widely from 8 % to 20,800 %. Strains below 100 % were achieved by uniaxial compression, while the high strains were obtained by the high-pressure torsion (HPT) technique. In addition to the as-built material, the same investigation was conducted on the alloy after heat treatment at 550 °C for 1 h after additive manufacturing. The as-built alloy had a fully body-centered cubic structure, while the annealing step resulted in the development of a hexagonal close-packed secondary α-Ti phase with a fraction of about 10 %. Compression up to a strain of 70 % resulted in an increase in the secondary phase fraction to 12 % and 22 % for the as-built and heat-treated alloys, respectively. HPT processing at high strains yielded a lower secondary phase fraction due to reverse martensitic transformation. The dislocation density increased to 70–100 × 10¹⁴ m⁻² when the strain rose to 70 % during compression. The dislocation density reached extremely large values of 600–700 × 10¹⁴ m⁻² at a strain of about 20,800 % achieved by HPT. Although the dislocation density increased by two orders of magnitude and nanocrystallization also occurred when the strain increased to 20,800 %, the hardness was enhanced only by 10–30 %. The unexpectedly low hardness increase after HPT was attributed to unique deformation mechanisms such as the kink pair related dislocation motion and grain boundary sliding.

研究了增材制造Ti-15%Nb-12%Zr （at.%）合金塑性变形过程中的显微组织演变。应用的等效应变范围极为广泛，从8%到20,800 %。通过单轴压缩获得低于100%的应变，而高压扭转（HPT）技术获得高应变。除了成品材料外，还对增材制造后550°C热处理1 h的合金进行了相同的研究。在退火过程中，生成的合金具有完全的体心立方结构，而在退火过程中，形成了六方密排的次生α-Ti相，其含量约为10%。当应变达到70%时，合金的二次相分数分别增加到12%和22%。在高应变条件下，由于反向马氏体转变，HPT加工产生了较低的二次相分数。压缩过程中，当应变增加到70%时，位错密度增加到70 ~ 100 × 1014 m−2。在HPT应变为20,800 %时，位错密度达到了600-700 × 1014 m−2的极大值。当应变增加到20,800 %时，虽然位错密度增加了两个数量级，并且出现了纳米晶化，但硬度仅提高了10 - 30%。HPT后硬度的低增长是由于独特的变形机制，如扭结对相关的位错运动和晶界滑动。

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引用次数: 0

Hydrogen embrittlement mitigation via microstructural and phase control in laser powder bed–fused SAF 3207 hyper duplex stainless steel 激光粉末床熔合SAF 3207超双相不锈钢的显微组织和相控制缓解氢脆

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-01-29 DOI: 10.1016/j.msea.2026.149861

Jalal Kangazian , Soung Yeoul Ahn , Bon Woo Koo , Jae Heung Lee , Man Jae SaGong , Renhao Wu , Do Won Lee , Longfei Xu , Ho Hyeong Lee , Dong-Woo Suh , Hyoung Seop Kim

Hydrogen embrittlement severely limits the reliability of duplex stainless steels (DSSs) exposed to hydrogen-rich or corrosive environments. This study correlates microstructure with performance, showing that post-heat treatment (HT) mitigates hydrogen embrittlement in SAF 3207 hyper DSS processed via laser-based powder bed fusion of metals (PBF-LB/M) additive manufacturing. The as-built (AB) microstructure consists of columnar δ-ferrite (≈74 %) decorated with nanoscale CrN precipitates and a minor fraction of γ-austenite (≈26 %), leading to high strength (≈1380 MPa) but limited ductility and pronounced hydrogen sensitivity. HT at 1150 °C transforms the AB structure into a near-balanced δ/γ duplex with reduced Cr nitrides (<0.5 %) and abundant annealing and deformation twins. This modification enhances the strength–ductility synergy through twinning-induced plasticity and hetero-deformation-induced back-stress hardening. Hydrogen charging of the AB and HTed samples alters both the mechanical response and fracture mode, leading to brittle fracture via the hydrogen-enhanced decohesion mechanism. Applying HT improved hydrogen embrittlement resistance, mainly by increasing the austenite fraction and disrupting ferrite connectivity, leading to kinetic immobilization of hydrogen. These findings establish phase balance and also twin boundary engineering as effective pathways for designing additively manufactured DSSs, leading to enhanced resistance to hydrogen-assisted failure under ex-situ charging.

氢脆严重限制了双相不锈钢（DSSs）暴露在富氢或腐蚀性环境中的可靠性。该研究将微观结构与性能联系起来，表明后热处理（HT）减轻了通过激光粉末床金属熔合（PBF-LB/M）增材制造加工的SAF 3207超DSS的氢脆。构建后的（AB）组织由柱状δ-铁素体（≈74%）和少量γ-奥氏体（≈26%）组成，表面装饰有纳米级CrN沉淀，具有较高的强度（≈1380 MPa），但延展性有限，氢敏感性明显。在1150℃高温下，AB结构转变为接近平衡的δ/γ双相，具有还原的Cr氮化物（< 0.5%）和丰富的退火和变形孪晶。这种改性通过孪生诱导塑性和异质变形诱导背应力硬化增强了强度-延性协同效应。氢对AB和HTed试样的充氢改变了试样的力学响应和断裂模式，通过氢增强脱粘机制导致试样脆性断裂。高温处理主要通过增加奥氏体分数和破坏铁素体连通性来提高氢的抗氢脆性，从而导致氢的动力学固定。这些发现表明，相平衡和双边界工程是设计增材制造DSSs的有效途径，可以增强其在非原位充电下对氢辅助失效的抵抗能力。

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引用次数: 0

The effect of arc welding-induced precipitation evolution on plastic deformation behavior in the 2195 Al-Cu-Li alloy heat-affected zone: Slip activation and slip transfer 电弧焊诱导析出演化对2195 Al-Cu-Li合金热影响区塑性变形行为的影响：滑移激活和滑移传递

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-02-02 DOI: 10.1016/j.msea.2026.149819

Qiang Wang , Dongfeng Shi , Quan Li , Zhilin Liu , Jin Zhang , Guoqing Wang

Arc welding heat input can introduce weakened zones known as heat-affected zones (HAZs) adjacent to the fusion zone (FZ) in the 2195 Al-Cu-Li alloy. The characteristics of HAZs are crucial for determining the overall performance of the welded joints. Herein, transmission electron microscopy (TEM) and quasi-in-situ electron backscatter diffraction (EBSD) were conducted to investigate the precipitation evolution, slip activation, and slip transfer behaviors in the base material (BM) and three typical HAZ subregions (HAZ₁, HAZ₂, HAZ₃). With decreasing distance from the FZ, θʹ precipitates undergo complete dissolution, while T₁ precipitates exhibit a reduction in number density and a non-monotonic change in average diameter (from 77 nm in BM to 55 nm in HAZ₁, then coarsening to 184 nm in HAZ₃). Grain boundary precipitates (GBPs) initially dissolve gradually, followed by the reprecipitation of coarse particles. Statistical analysis of slip traces in 350 grains and slip transfer across 300 grain boundaries in the BM and three typical HAZ subregions during plastic deformation revealed that a lower density of strengthening precipitates delays the activation of multiple slip systems. This delay leads to more homogeneous variations in grain orientation and enhanced intragranular deformability. Furthermore, the progressive dissolution of GBPs increases the proportion of slip transfer, rising from 5.4% in the BM to 13.7% in HAZ₂. However, the coarsely reprecipitated GBPs in HAZ₃ adjacent to the FZ act as strong obstacles to dislocation glide and slip transfer, thereby reducing the proportion of slip transfer to 5.2% and limiting intergranular deformation coordination. These experimental findings help to further reveal the effect of welding heat input on precipitation evolution and deformation mechanisms in the HAZ, and provide insights into optimizing the welding process for the 2195 Al-Cu-Li alloy.

在2195 Al-Cu-Li合金中，弧焊热输入会在熔合区（FZ）附近引入被称为热影响区（haz）的弱化区。haz的特性是决定焊接接头整体性能的关键。利用透射电子显微镜（TEM）和准原位电子背散射衍射（EBSD）研究了基材（BM）和三个典型HAZ亚区（HAZ1、HAZ2、HAZ3）中的析出演化、滑移激活和滑移转移行为。随着离熔点距离的减小，θ′′相完全溶解，T1相数量密度减小，平均直径呈非单调变化（从BM的77 nm到HAZ1的55 nm，再到HAZ3的184 nm）。晶界析出物（GBPs）最初逐渐溶解，然后再析出粗颗粒。在塑性变形过程中，对BM和三个典型热影响区350个晶界的滑移轨迹和300个晶界的滑移传递进行统计分析表明，较低密度的强化相延迟了多个滑移系统的激活。这种延迟导致晶粒取向更均匀的变化和增强的晶内变形能力。此外，GBPs的逐渐溶解增加了滑移转移的比例，从BM的5.4%上升到HAZ2的13.7%。然而，靠近FZ的HAZ3中粗重析出的GBPs对位错滑动和滑移转移起到了强大的阻碍作用，使滑移转移比例降至5.2%，限制了晶间变形协调。这些实验结果有助于进一步揭示焊接热输入对热影响区析出演变和变形机制的影响，为2195 Al-Cu-Li合金焊接工艺的优化提供参考。

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引用次数: 0

Mitigating the challenges in additive manufacturing of refractory complex concentrated alloys using Ti alloying via multi-material feedstock approach 采用多材料给料方法，采用Ti合金化技术，减轻了复合难熔浓缩合金增材制造的挑战

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-01-30 DOI: 10.1016/j.msea.2026.149867

Magesh Kumaravel , Joachim Gussone , Meaghi Sikder , Amir Ardeshiri Lordejani , Ida S. Berglund , Jan Haubrich , Sara Bagherifard , Mario Guagliano

The development of novel refractory complex concentrated alloy material systems for extreme environments, despite the promise, is hindered by significant processing challenges during fabrication. These challenges primarily stem from their intrinsic properties: high hardness and brittle nature restrict deposition through impact-based approaches such as cold spray additive manufacturing (CSAM), while the wide variation in melting temperatures among constituent elements limits the processability by melting and solidification - based additive manufacturing techniques such as laser-based powder bed fusion (LB-PBF). In this study, a composite feedstock approach was employed to mitigate the aforementioned-challenges during CSAM and LB-PBF processing. Commercially pure Ti was employed as the secondary material and was mixed with a custom-developed TaNbTiVCr alloy at varying volumetric ratios. The CSAM and LB-PBF printed specimens were systematically characterized in terms of their microstructure and microhardness. CSAM and LB-PBF printed specimens with different volume fractions of mixing demonstrated excellent build quality, with negligible porosity and crack formations, albeit with inhomogeneous microstructures. In the case of CSAM, the specimen with highest TaNbTiVCr content retained comparable hardness to that of the feedstock powder, despite Ti addition. The Ti particles offered a cushioning effect to the impacting TaNbTiVCr particles, thereby limiting the inter-particle interaction between them, aiding the deposit build-up. On the other hand, Ti addition for the LB-PBF processing played a critical role in inhibiting the formation of hot-cracks and lack-of-fusion porosities. However, this was at an expense of lower hardness compared to the CSAM counterparts. Overall, this systematic study highlights the potential of employing a composite feedstock approach to significantly enhance the processability of the complex refractory alloys through additive manufacturing.

用于极端环境的新型难熔复杂浓缩合金材料系统的发展，尽管有希望，但在制造过程中受到重大加工挑战的阻碍。这些挑战主要源于它们的固有特性：高硬度和脆性限制了冷喷涂增材制造（CSAM）等基于冲击的方法的沉积，而组成元素之间熔化温度的广泛变化限制了基于熔化和凝固的增材制造技术的可加工性，如基于激光的粉末床熔化（LB-PBF）。在本研究中，采用复合原料方法来缓解CSAM和LB-PBF加工过程中的上述挑战。采用商业纯钛作为次级材料，并以不同的体积比与定制开发的TaNbTiVCr合金混合。对CSAM和LB-PBF打印样品的微观结构和显微硬度进行了系统表征。不同体积分数混合的CSAM和LB-PBF打印样品显示出出色的构建质量，尽管微观结构不均匀，但气孔和裂纹的形成可以忽略不计。在CSAM的情况下，尽管添加了Ti，但具有最高TaNbTiVCr含量的试样仍保持与原料粉末相当的硬度。Ti颗粒对撞击的TaNbTiVCr颗粒起到缓冲作用，从而限制了颗粒间的相互作用，有助于沉积。另一方面，在LB-PBF中添加Ti对抑制热裂纹的形成和缺乏熔合的孔隙率起着关键作用。然而，与CSAM相比，这是以硬度较低为代价的。总的来说，这项系统的研究强调了采用复合原料方法通过增材制造显着提高复杂耐火合金的可加工性的潜力。

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引用次数: 0

Using severe warm caliber rolling (SWCR) to obtain heterostructured titanium alloy 采用超温管径轧制（SWCR）法制备异质组织钛合金

IF 7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Science and Engineering: A

Pub Date : 2026-03-01 Epub Date: 2026-02-06 DOI: 10.1016/j.msea.2026.149872

Baoxi Liu , Wenhao Zhao , Chuan Wu , Mengbang Ding , Xiangpeng Deng , Puguang Ji , Fuxing Yin

Severe warm caliber rolling (SWCR) at 700 °C (87% reduction) produced a 0.2 μm heterostructure in Ti6554 alloy via continuous geometric dynamic recrystallization. Aging at 525 °C/4h yielded 1630 MPa strength, 11.7% elongation, 385-555% superplasticity (600-750 °C), and delamination toughening started above 200°C, offering a new design strategy for ultrafine multiphase materials.

700℃高温热径轧制（SWCR）使Ti6554合金通过连续的几何动态再结晶形成0.2 μm异质组织。在525°C/4h时效下，强度为1630 MPa，伸长率为11.7%，超塑性为385-555%(600-750°C)，在200°C以上开始分层增韧，为超细多相材料的设计提供了新的策略。

引用次数: 0