Materials Science and Engineering: A最新文献

Effects of σ phase embrittlement and Al addition on the ductile-brittle transition in super ferritic stainless steels σ相脆化和添加铝对超级铁素体不锈钢韧性-脆性转变的影响

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

Materials Science and Engineering: A

Pub Date : 2024-11-18 DOI: 10.1016/j.msea.2024.147564

Ling-Yun Du , Hui-Hu Lu , Ze-Zhou Xing , Yi-Nan Wang , Jian-Shan Han , Yong-Zou

The precipitation evolution and mechanical behaviour of Al-modified and Al-free super ferritic stainless steels (SFSSs) subjected to hot-rolling and isothermal aging at 850 °C were investigated comparatively. Experimental results revealed that hot-rolled samples devoid of Al exhibited elongated fibre microstructure including many sub-grain boundaries and shear bands, whereas a surface recrystallization layer was observed in Al-modified samples. During isothermal aging, σ, χ, and Laves phases were observed in Al-free samples, whereas primarily Laves phases and a small σ phase were identified in 1.0 wt%Al samples. Rolling deformation accelerated the σ phase precipitation kinetic, whereas the addition of Al inhibited σ phase precipitation and promoted Laves-phase precipitation. The bulky σ phase precipitation caused the cleavage fracture in SFSSs owing to the high critical resolved shear stress for dislocation glide on {110}<001>, {100}<001>, {100}<010>, and {111}<0-11> slip systems and the easy crack initiation and propagation in the σ phase during tensile test. Despite being aged for 16 h, Al-modified SFSSs exhibited a significant elongation of 22.6 %. This study highlights that Al addition would facilitate not only the low-temperature hot rolling of SFSSs but also SFSS production without the need for solution treatment prior to cold rolling, thereby offering a promising short-process approach for industrial manufacturing.

对比研究了经 850 °C 热轧和等温时效处理的铝改性和无铝超级铁素体不锈钢（SFSS）的析出演变和机械性能。实验结果表明，不含铝的热轧样品表现出拉长的纤维微观结构，包括许多亚晶界和剪切带，而在铝改性样品中则观察到表面再结晶层。在等温老化过程中，在无铝样品中观察到 σ、χ 和 Laves 相，而在 1.0 wt%Al 样品中主要发现了 Laves 相和少量 σ 相。滚动变形加速了 σ 相的析出动力学，而添加 Al 则抑制了 σ 相的析出，促进了 Laves 相的析出。由于在{110}<001>、{100}<001>、{100}<010>和{111}<0-11>滑移体系中位错滑行的临界分解剪切应力较高，以及在拉伸试验中σ相中裂纹容易发生和扩展，因此大量σ相析出导致了 SFSS 的劈裂断裂。尽管经过了 16 小时的老化，铝改性 SFSS 仍表现出 22.6% 的显著伸长率。这项研究表明，添加 Al 不仅有利于 SFSS 的低温热轧，还有利于 SFSS 的生产，而无需在冷轧前进行固溶处理，从而为工业生产提供了一种前景广阔的短流程方法。

{"title":"Effects of σ phase embrittlement and Al addition on the ductile-brittle transition in super ferritic stainless steels","authors":"Ling-Yun Du , Hui-Hu Lu , Ze-Zhou Xing , Yi-Nan Wang , Jian-Shan Han , Yong-Zou","doi":"10.1016/j.msea.2024.147564","DOIUrl":"10.1016/j.msea.2024.147564","url":null,"abstract":"<div><div>The precipitation evolution and mechanical behaviour of Al-modified and Al-free super ferritic stainless steels (SFSSs) subjected to hot-rolling and isothermal aging at 850 °C were investigated comparatively. Experimental results revealed that hot-rolled samples devoid of Al exhibited elongated fibre microstructure including many sub-grain boundaries and shear bands, whereas a surface recrystallization layer was observed in Al-modified samples. During isothermal aging, σ, χ, and Laves phases were observed in Al-free samples, whereas primarily Laves phases and a small σ phase were identified in 1.0 wt%Al samples. Rolling deformation accelerated the σ phase precipitation kinetic, whereas the addition of Al inhibited σ phase precipitation and promoted Laves-phase precipitation. The bulky σ phase precipitation caused the cleavage fracture in SFSSs owing to the high critical resolved shear stress for dislocation glide on {110}<001>, {100}<001>, {100}<010>, and {111}<0-11> slip systems and the easy crack initiation and propagation in the σ phase during tensile test. Despite being aged for 16 h, Al-modified SFSSs exhibited a significant elongation of 22.6 %. This study highlights that Al addition would facilitate not only the low-temperature hot rolling of SFSSs but also SFSS production without the need for solution treatment prior to cold rolling, thereby offering a promising short-process approach for industrial manufacturing.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147564"},"PeriodicalIF":6.1,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663349","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

Precipitation and TRIP enhanced spallation resistance of additive manufactured M350 steel 沉淀和 TRIP 增强了添加剂制造的 M350 钢的抗剥落性

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

Materials Science and Engineering: A

Pub Date : 2024-11-16 DOI: 10.1016/j.msea.2024.147547

Xiaotian Yao , Qiannan Wang , Sen Chen , Yuan Wang , Siyuan Wei , Kwang Boon Lau , Pei Wang , Chengda Dai , Jianbo Hu

This work investigates the spall damage and microstructural deformation behaviors of a heat-treated, hierarchical structured 18 wt% Ni-350 maraging steel (M350) produced by laser powder bed fusion (LPBF) under shock loading. The samples were shock-loaded along different orientations with peak shock stresses ranging from 7.0 GPa to 10.5 GPa. Experimental results demonstrate that the M350 exhibits ultra-high spall strength of 5.01–5.89 GPa and 4.53–4.99 GPa when loading perpendicularly and parallel to the building direction, respectively. Spall damage is characterized as a typical transgranular brittle fracture with {100} cleavage planes within the block. The observed superior mechanical performance is attributed to the precipitation strengthening and the transformation-induced plasticity (TRIP) effect. Dislocation slip cuts through the Ni₃Ti precipitates, causing them to fracture, simultaneously, high density precipitates impede dislocation movement according to the Orowan mechanism, preventing the formation of microcracks. The residual austenite undergoes martensitic transformation with the formation of new secondary laths with widths of 20–60 nm to accommodate localized plastic deformations, which creates a large number of grain boundaries and leads to grain refinement.

本研究探讨了激光粉末床熔融（LPBF）生产的热处理分层结构 18 wt% Ni-350 马氏体时效钢（M350）在冲击载荷下的剥落损伤和微结构变形行为。样品沿不同方向受到冲击加载，冲击应力峰值为 7.0 GPa 至 10.5 GPa。实验结果表明，当垂直和平行于建筑方向加载时，M350 表现出超高的剥落强度，分别为 5.01-5.89 GPa 和 4.53-4.99 GPa。剥落破坏的特征是典型的跨晶脆性断裂，块体内部有{100}劈裂面。观察到的优异机械性能归因于沉淀强化和转化诱导塑性（TRIP）效应。位错滑移穿过 Ni3Ti 沉淀，导致其断裂，同时，高密度沉淀根据奥罗恩机制阻碍了位错运动，防止了微裂纹的形成。残余奥氏体发生马氏体转变，形成宽度为 20-60 nm 的新次生板条，以适应局部塑性变形，从而形成大量晶界，导致晶粒细化。

{"title":"Precipitation and TRIP enhanced spallation resistance of additive manufactured M350 steel","authors":"Xiaotian Yao , Qiannan Wang , Sen Chen , Yuan Wang , Siyuan Wei , Kwang Boon Lau , Pei Wang , Chengda Dai , Jianbo Hu","doi":"10.1016/j.msea.2024.147547","DOIUrl":"10.1016/j.msea.2024.147547","url":null,"abstract":"<div><div>This work investigates the spall damage and microstructural deformation behaviors of a heat-treated, hierarchical structured 18 wt% Ni-350 maraging steel (M350) produced by laser powder bed fusion (LPBF) under shock loading. The samples were shock-loaded along different orientations with peak shock stresses ranging from 7.0 GPa to 10.5 GPa. Experimental results demonstrate that the M350 exhibits ultra-high spall strength of 5.01–5.89 GPa and 4.53–4.99 GPa when loading perpendicularly and parallel to the building direction, respectively. Spall damage is characterized as a typical transgranular brittle fracture with {100} cleavage planes within the block. The observed superior mechanical performance is attributed to the precipitation strengthening and the transformation-induced plasticity (TRIP) effect. Dislocation slip cuts through the Ni<sub>3</sub>Ti precipitates, causing them to fracture, simultaneously, high density precipitates impede dislocation movement according to the Orowan mechanism, preventing the formation of microcracks. The residual austenite undergoes martensitic transformation with the formation of new secondary laths with widths of 20–60 nm to accommodate localized plastic deformations, which creates a large number of grain boundaries and leads to grain refinement.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147547"},"PeriodicalIF":6.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663401","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

Thermo-mechanical response and form-stability of a fully metallic composite phase change material: Dilatometric tests and finite element analysis 全金属复合相变材料的热机械响应和形状稳定性：稀释试验和有限元分析

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

Materials Science and Engineering: A

Pub Date : 2024-11-15 DOI: 10.1016/j.msea.2024.147562

Elisabetta Gariboldi , Matteo Molteni , Diego Andree Vargas Vargas , Konstantin Naumenko

Composite Phase Change Materials (C-PCMs), such as immiscible Al-Sn alloys are designed to store and release heat as a result of the phase transformation of one of the phases, i.e., Sn in this case. The volume changes induced by melting and solidification of the low-melting Sn phase as well as the different thermal expansion of solid Al and Sn phases induces stress fields during thermal cycles. Repeated experimental dilatometric tests were performed on the above C-PCM to check their microstructural stability as well as its effect on their form-stability, i.e., capability to recover the initial shape under various potential cyclic service conditions.

Analysis of the thermo-mechanical behaviour of the two phases, as well as the overall one, have been investigated under the simple thermal profiles reproducing dilatometric tests. A finite element model of fully dense Al-Sn C-PCM, where a single spherical inclusion of Sn is surrounded by Al matrix, is generated and numerical thermo-mechanical analysis is performed. The thermal-dependence of elastoplastic-behaviour, thermal expansivity and other thermophysical properties of the 2 solid phases has been modelled, together with compressibility of liquid Sn. The simulations illustrate the overall material behaviour as well as the local thermomechanical response. The results for the slopes of elongation vs temperature curves agree well with experimental data from dilatometric tests, for which form-stability is observed from the third cycle. The results also suggested that the plastic deformation of the only regions of Al phase surrounding the Sn inclusion accommodates its expansion during heating and melting. In these latter regions, at the end of a dilatometric cycle, compressive strain in radial direction reaches a maximum value of 0.1 %, higher than overall strains.

复合相变材料（C-PCMs），例如不相溶的铝锡合金，其设计目的是通过其中一种相（即本例中的锡相）的相变来储存和释放热量。低熔点锡相的熔化和凝固引起的体积变化以及固态铝相和锡相的不同热膨胀在热循环过程中会产生应力场。对上述 C-PCM 进行了反复的膨胀试验，以检查其微观结构稳定性及其对形状稳定性的影响，即在各种潜在的循环使用条件下恢复初始形状的能力。生成了全致密 Al-Sn C-PCM 的有限元模型，并进行了数值热机械分析。模拟了两种固相的弹塑性行为、热膨胀系数和其他热物理性质的热依赖性，以及液态锡的可压缩性。模拟结果表明了材料的整体行为和局部热机械响应。伸长率与温度曲线的斜率结果与膨胀试验的实验数据非常吻合，从第三个周期开始就能观察到其形状稳定性。研究结果还表明，在加热和熔化过程中，锡夹杂物周围仅有的铝相区域的塑性变形可容纳锡夹杂物的膨胀。在后者的这些区域，在稀释周期结束时，径向压缩应变达到最大值 0.1%，高于整体应变。

{"title":"Thermo-mechanical response and form-stability of a fully metallic composite phase change material: Dilatometric tests and finite element analysis","authors":"Elisabetta Gariboldi , Matteo Molteni , Diego Andree Vargas Vargas , Konstantin Naumenko","doi":"10.1016/j.msea.2024.147562","DOIUrl":"10.1016/j.msea.2024.147562","url":null,"abstract":"<div><div>Composite Phase Change Materials (C-PCMs), such as immiscible Al-Sn alloys are designed to store and release heat as a result of the phase transformation of one of the phases, i.e., Sn in this case. The volume changes induced by melting and solidification of the low-melting Sn phase as well as the different thermal expansion of solid Al and Sn phases induces stress fields during thermal cycles. Repeated experimental dilatometric tests were performed on the above C-PCM to check their microstructural stability as well as its effect on their form-stability, i.e., capability to recover the initial shape under various potential cyclic service conditions.</div><div>Analysis of the thermo-mechanical behaviour of the two phases, as well as the overall one, have been investigated under the simple thermal profiles reproducing dilatometric tests. A finite element model of fully dense Al-Sn C-PCM, where a single spherical inclusion of Sn is surrounded by Al matrix, is generated and numerical thermo-mechanical analysis is performed. The thermal-dependence of elastoplastic-behaviour, thermal expansivity and other thermophysical properties of the 2 solid phases has been modelled, together with compressibility of liquid Sn. The simulations illustrate the overall material behaviour as well as the local thermomechanical response. The results for the slopes of elongation vs temperature curves agree well with experimental data from dilatometric tests, for which form-stability is observed from the third cycle. The results also suggested that the plastic deformation of the only regions of Al phase surrounding the Sn inclusion accommodates its expansion during heating and melting. In these latter regions, at the end of a dilatometric cycle, compressive strain in radial direction reaches a maximum value of 0.1 %, higher than overall strains.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147562"},"PeriodicalIF":6.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The effects of loading direction on the dynamic impact response of additively manufactured M350 maraging steel-Al0.5CoCrFeNi1.5 hybrid plates 加载方向对快速成型 M350 马氏体时效钢-Al0.5 钴铬铁镍 1.5 混合板材动态冲击响应的影响

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

Materials Science and Engineering: A

Pub Date : 2024-11-14 DOI: 10.1016/j.msea.2024.147541

T.N. Odiaka , G. Asala , O.T. Ola , O.A. Ojo , I.N.A. Oguocha , A.G. Odeshi

Despite the impressive impact strength of maraging steels, which informs their application in the defence industry, they are highly susceptible to cracking resulting from adiabatic shear band (ASB) nucleation when subjected to dynamic loading. Hence, a potential solution to mitigate this problem is needed. In this study, a hybrid plate containing layers of M350 maraging steel and Al_0.5CoCrFeNi_1.5 high entropy alloy was fabricated using laser-based directed energy deposition (L-DED) additive manufacturing with the aim of combining the high impact strength of M350 maraging steel with the ductility and ASB-resistant properties of Al_0.5CoCrFeNi_1.5. To determine the effect of loading direction on the impact strength and absorbed energy of the hybrid specimens, cylindrical specimens, with the layers oriented longitudinally and transversely to the cylinder's axis, were cut out of the hybrid plate. High-strain rate testing was performed using an instrumented split-Hopkinson pressure bar (SHPB) to determine the dynamic mechanical response of the specimens. Statistical analyses of the results using generalised additive models (GAM) showed that layer orientation with respect to the direction of impact significantly affects the hybrid specimens' impact strength and absorbed energy. The longitudinally oriented specimens demonstrated superior impact strength across all tested impact momenta. However, the transversely oriented specimens showed higher absorbed energy up to an impact momentum of 32.8 kg ms⁻¹. The Al_0.5CoCrFeNi_1.5 layer contributed significantly to energy absorption, strain hardening, and the inhibition of ASB propagation in the hybrid specimens.

尽管马氏体时效钢的冲击强度令人印象深刻，这也是其在国防工业中应用的基础，但在承受动态载荷时，它们极易因绝热剪切带（ASB）成核而开裂。因此，需要一种潜在的解决方案来缓解这一问题。在本研究中，使用基于激光的定向能沉积（L-DED）增材制造技术制造了一种包含 M350 马氏体时效钢和 Al0.5CoCrFeNi1.5 高熵合金层的混合板，旨在将 M350 马氏体时效钢的高冲击强度与 Al0.5CoCrFeNi1.5 的延展性和抗 ASB 性能结合起来。为了确定加载方向对混合试样冲击强度和吸收能量的影响，从混合板上切割出圆柱形试样，试样层的方向与圆柱轴线呈纵向和横向。使用带仪器的分体式霍普金森压力棒（SHPB）进行高应变速率测试，以确定试样的动态机械响应。使用广义相加模型（GAM）对结果进行的统计分析显示，相对于冲击方向的层取向会显著影响混合试样的冲击强度和吸收能量。纵向取向试样在所有测试的冲击力矩下都表现出优异的冲击强度。然而，横向取向的试样在 32.8 kg ms-1 的冲击动量下吸收的能量更高。混合试样中的 Al0.5CoCrFeNi1.5 层在能量吸收、应变硬化和抑制 ASB 扩展方面做出了重大贡献。

{"title":"The effects of loading direction on the dynamic impact response of additively manufactured M350 maraging steel-Al0.5CoCrFeNi1.5 hybrid plates","authors":"T.N. Odiaka , G. Asala , O.T. Ola , O.A. Ojo , I.N.A. Oguocha , A.G. Odeshi","doi":"10.1016/j.msea.2024.147541","DOIUrl":"10.1016/j.msea.2024.147541","url":null,"abstract":"<div><div>Despite the impressive impact strength of maraging steels, which informs their application in the defence industry, they are highly susceptible to cracking resulting from adiabatic shear band (ASB) nucleation when subjected to dynamic loading. Hence, a potential solution to mitigate this problem is needed. In this study, a hybrid plate containing layers of M350 maraging steel and Al<sub>0.5</sub>CoCrFeNi<sub>1.5</sub> high entropy alloy was fabricated using laser-based directed energy deposition (L-DED) additive manufacturing with the aim of combining the high impact strength of M350 maraging steel with the ductility and ASB-resistant properties of Al<sub>0.5</sub>CoCrFeNi<sub>1.5</sub>. To determine the effect of loading direction on the impact strength and absorbed energy of the hybrid specimens, cylindrical specimens, with the layers oriented longitudinally and transversely to the cylinder's axis, were cut out of the hybrid plate. High-strain rate testing was performed using an instrumented split-Hopkinson pressure bar (SHPB) to determine the dynamic mechanical response of the specimens. Statistical analyses of the results using generalised additive models (GAM) showed that layer orientation with respect to the direction of impact significantly affects the hybrid specimens' impact strength and absorbed energy. The longitudinally oriented specimens demonstrated superior impact strength across all tested impact momenta. However, the transversely oriented specimens showed higher absorbed energy up to an impact momentum of 32.8 kg ms<sup>−1</sup>. The Al<sub>0.5</sub>CoCrFeNi<sub>1.5</sub> layer contributed significantly to energy absorption, strain hardening, and the inhibition of ASB propagation in the hybrid specimens.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147541"},"PeriodicalIF":6.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel strategy for preparing gradient grained Mg alloy by normal extrusion process 利用普通挤压工艺制备梯度晶粒镁合金的新策略

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

Materials Science and Engineering: A

Pub Date : 2024-11-14 DOI: 10.1016/j.msea.2024.147557

Peng Peng , Shibo Zhou , Jia She , Aitao Tang , Shuai Long , Qingshan Yang , Qingwei Dai , Jianyue Zhang , Fusheng Pan

A novel strategy for fabricating gradient-grained Mg alloys, consisting of equiaxed ultrafine grains (UFG) and bimodal grains, has been developed through normal extrusion processing of the Mg-Mn binary alloy. The gradient-grained structure was created by a gradient strain field from a stepped structure in extrusion die. The gradient strain leads to the foundation for subsequent gradient grain nucleation and also prompts the occurrence of dynamic precipitates at the low angle grain boundaries, which is also distributed in a gradient manner and plays a vital role in impeding grain boundary migration. By combining gradient nucleation and pinning effect, a gradient microstructure is successfully achieved in the Mg-2.0Mn binary alloy using the normal extrusion process. The Mg-2.0Mn alloy with a gradient-grain structure, exhibits exceptional mechanical strength and ductility. The presence of the gradient structure effectively enhances the work-hardening rate, attributed to the synergistic effect of the ultrafine and bimodal grains.

通过对镁锰二元合金进行正常挤压加工，开发出了一种制造梯度晶粒镁合金的新策略，该合金由等轴超细晶粒（UFG）和双峰晶粒组成。梯度晶粒结构是由挤压模具中的阶梯结构产生的梯度应变场形成的。梯度应变为随后的梯度晶粒成核奠定了基础，同时也促使低角度晶界出现动态沉淀，这种沉淀也以梯度方式分布，在阻碍晶界迁移方面发挥了重要作用。通过将梯度成核和针刺效应相结合，利用普通挤压工艺成功地在 Mg-2.0Mn 二元合金中实现了梯度微观结构。具有梯度晶粒结构的 Mg-2.0Mn 合金具有优异的机械强度和延展性。梯度结构的存在有效提高了加工硬化率，这归功于超细晶粒和双峰晶粒的协同效应。

{"title":"A novel strategy for preparing gradient grained Mg alloy by normal extrusion process","authors":"Peng Peng , Shibo Zhou , Jia She , Aitao Tang , Shuai Long , Qingshan Yang , Qingwei Dai , Jianyue Zhang , Fusheng Pan","doi":"10.1016/j.msea.2024.147557","DOIUrl":"10.1016/j.msea.2024.147557","url":null,"abstract":"<div><div>A novel strategy for fabricating gradient-grained Mg alloys, consisting of equiaxed ultrafine grains (UFG) and bimodal grains, has been developed through normal extrusion processing of the Mg-Mn binary alloy. The gradient-grained structure was created by a gradient strain field from a stepped structure in extrusion die. The gradient strain leads to the foundation for subsequent gradient grain nucleation and also prompts the occurrence of dynamic precipitates at the low angle grain boundaries, which is also distributed in a gradient manner and plays a vital role in impeding grain boundary migration. By combining gradient nucleation and pinning effect, a gradient microstructure is successfully achieved in the Mg-2.0Mn binary alloy using the normal extrusion process. The Mg-2.0Mn alloy with a gradient-grain structure, exhibits exceptional mechanical strength and ductility. The presence of the gradient structure effectively enhances the work-hardening rate, attributed to the synergistic effect of the ultrafine and bimodal grains.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147557"},"PeriodicalIF":6.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663350","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

Conspicuous rejuvenation of plasma-assisted hydrogenated Zr-based bulk metallic glasses via deep cryogenic cycling treatment 通过深低温循环处理实现等离子体辅助氢化锆基块状金属玻璃的明显年轻化

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

Materials Science and Engineering: A

Pub Date : 2024-11-14 DOI: 10.1016/j.msea.2024.147559

Guishen Zhou , Yuexin Chu , Fuyu Dong , Yue Zhang , Kun Liu , Binbin Wang , Liangshun Luo , Yanqing Su , Xiaoguang Yuan , Weidong Li , Peter K. Liaw , Jun Cheng

To obtain a greater degree of a deep cryogenic cycle treatment (DCT)-induced rejuvenation, Zr-based bulk metallic glass samples were prepared under a mixed argon/hydrogen atmosphere prior to the deep cryogenic cycling treatment. The degree of rejuvenation is quantified by the increase of relaxation enthalpy ΔH_rel measured by differential scanning calorimetry (DSC). The purpose of this pretreatment was to change the chemical heterogeneity through the in situ absorption of hydrogen during melting and solidification. It was found that the hydrogenated specimens were more sensitive to DCT and exceeded the rejuvenation upper limit of uncharged specimens. The results were compared with previous reports, which further highlighted the distinctive advantage of the H-charged specimens for DCT. Furthermore, the plasticity of the hydrogenated metallic glass was enhanced significantly after DCT, as supported by hardness, compression ductility, and nanoindentation creep data. It is crucial to understand that DCT-induced rejuvenation is related to the content of hydrogen and may provide a new avenue to improve the mechanical properties or functional characteristics of BMG.

为了获得更大程度的深低温循环处理（DCT）诱导的年轻化，在进行深低温循环处理之前，在氩气/氢气混合气氛下制备了锆基块状金属玻璃样品。通过差示扫描量热仪（DSC）测量弛豫焓 ΔHrel 的增加来量化年轻化程度。这种预处理的目的是通过在熔化和凝固过程中原位吸收氢来改变化学异质性。研究发现，氢化试样对 DCT 更为敏感，并且超过了未带电试样的再生上限。研究结果与之前的报告进行了比较，进一步凸显了充氢试样在 DCT 方面的独特优势。此外，氢化金属玻璃的塑性在 DCT 之后显著增强，硬度、压缩延展性和纳米压痕蠕变数据都证明了这一点。关键是要了解 DCT 诱导的年轻化与氢含量有关，这可能为改善 BMG 的机械性能或功能特性提供了一条新途径。

{"title":"Conspicuous rejuvenation of plasma-assisted hydrogenated Zr-based bulk metallic glasses via deep cryogenic cycling treatment","authors":"Guishen Zhou , Yuexin Chu , Fuyu Dong , Yue Zhang , Kun Liu , Binbin Wang , Liangshun Luo , Yanqing Su , Xiaoguang Yuan , Weidong Li , Peter K. Liaw , Jun Cheng","doi":"10.1016/j.msea.2024.147559","DOIUrl":"10.1016/j.msea.2024.147559","url":null,"abstract":"<div><div>To obtain a greater degree of a deep cryogenic cycle treatment (DCT)-induced rejuvenation, Zr-based bulk metallic glass samples were prepared under a mixed argon/hydrogen atmosphere prior to the deep cryogenic cycling treatment. The degree of rejuvenation is quantified by the increase of relaxation enthalpy Δ<em>H</em><sub>rel</sub> measured by differential scanning calorimetry (DSC). The purpose of this pretreatment was to change the chemical heterogeneity through the <em>in situ</em> absorption of hydrogen during melting and solidification. It was found that the hydrogenated specimens were more sensitive to DCT and exceeded the rejuvenation upper limit of uncharged specimens. The results were compared with previous reports, which further highlighted the distinctive advantage of the H-charged specimens for DCT. Furthermore, the plasticity of the hydrogenated metallic glass was enhanced significantly after DCT, as supported by hardness, compression ductility, and nanoindentation creep data. It is crucial to understand that DCT-induced rejuvenation is related to the content of hydrogen and may provide a new avenue to improve the mechanical properties or functional characteristics of BMG.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147559"},"PeriodicalIF":6.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663403","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

Simultaneously achieving strength-ductility in additive-manufactured Ti6Al4V alloy via ultrasonic surface rolling process 通过超声波表面轧制工艺同时实现添加剂制造的 Ti6Al4V 合金的强度和电导率

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

Materials Science and Engineering: A

Pub Date : 2024-11-14 DOI: 10.1016/j.msea.2024.147555

Changhao Zhou , Xinyu Yan , Dan Liu , Xingchen Xu , Junfeng Cui , Mengyao Li , Chun Yuan , Hairong Li , Yilong Liang

Additively manufactured alloys have a great potential in engineering field, but there still have many issues to be addressed, i.e., the reliability, strength-ductility trade-off of manufactured parts. In this study, a treatment called ultrasonic surface rolling process (USRP) was utilized to achieve superior strength and ductility in the Ti6Al4V alloy prepared via electron beam melting (EBM). The treated additive-manufactured alloy obtained various gradient microstructures and excellent surface quality, as well as its mechanical properties were significantly improved. Especially, the USRP-3 specimen exhibited a high elongation of 17.1 ± 0.9 % and a good ultimate tensile strength of 1043 ± 5.0 MPa, which were both higher than those of untreated specimen; the fine laminated structure with a preferred orientation of (

10 \overline{1} 0

) direction and gradient structure promoted the hardening capacity and provided the rich dislocations sources, taking a better strength-ductility combination. In addition, the surface microhardness of the multi-pass processed specimen was markedly enhanced. However, excessive USRP treatment would induce micro-cracks in the nano-composite layer, resulting in a significant reduction in ductility. Therefore, appropriate USRP treatment is expected to expand the application range of additive-manufactured metallic materials.

添加式制造合金在工程领域具有巨大潜力，但仍有许多问题需要解决，如制造部件的可靠性、强度-韧性权衡等。本研究利用超声波表面滚压工艺（USRP）对通过电子束熔化（EBM）制备的 Ti6Al4V 合金进行处理，以获得优异的强度和延展性。经过处理的添加剂制造合金获得了各种梯度微结构和优异的表面质量，其机械性能也得到了显著改善。尤其是 USRP-3 试样的伸长率高达 17.1 ± 0.9 %，极限抗拉强度为 1043 ± 5.0 MPa，均高于未处理试样；优选取向为（101‾0）方向的细层状结构和梯度结构提高了淬透性，并提供了丰富的位错源，使其具有更好的强度-电导率组合。此外，多道处理试样的表面显微硬度也明显提高。然而，过度的 USRP 处理会在纳米复合材料层中产生微裂纹，导致延展性显著降低。因此，适当的 USRP 处理有望扩大添加剂制造金属材料的应用范围。

{"title":"Simultaneously achieving strength-ductility in additive-manufactured Ti6Al4V alloy via ultrasonic surface rolling process","authors":"Changhao Zhou , Xinyu Yan , Dan Liu , Xingchen Xu , Junfeng Cui , Mengyao Li , Chun Yuan , Hairong Li , Yilong Liang","doi":"10.1016/j.msea.2024.147555","DOIUrl":"10.1016/j.msea.2024.147555","url":null,"abstract":"<div><div>Additively manufactured alloys have a great potential in engineering field, but there still have many issues to be addressed, i.e., the reliability, strength-ductility trade-off of manufactured parts. In this study, a treatment called ultrasonic surface rolling process (USRP) was utilized to achieve superior strength and ductility in the Ti6Al4V alloy prepared via electron beam melting (EBM). The treated additive-manufactured alloy obtained various gradient microstructures and excellent surface quality, as well as its mechanical properties were significantly improved. Especially, the USRP-3 specimen exhibited a high elongation of 17.1 ± 0.9 % and a good ultimate tensile strength of 1043 ± 5.0 MPa, which were both higher than those of untreated specimen; the fine laminated structure with a preferred orientation of (<span><math><mrow><mn>10</mn><mover><mn>1</mn><mo>‾</mo></mover><mn>0</mn></mrow></math></span>) direction and gradient structure promoted the hardening capacity and provided the rich dislocations sources, taking a better strength-ductility combination. In addition, the surface microhardness of the multi-pass processed specimen was markedly enhanced. However, excessive USRP treatment would induce micro-cracks in the nano-composite layer, resulting in a significant reduction in ductility. Therefore, appropriate USRP treatment is expected to expand the application range of additive-manufactured metallic materials.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147555"},"PeriodicalIF":6.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663400","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

Effects of pre-heating induced interfacial diffusion on microstructure and related mechanical properties of direct laser metal deposited Inconel 625 superalloy on a Cu-Cr-Zr substrate 预热诱导的界面扩散对 Cu-Cr-Zr 基底上直接激光金属沉积 Inconel 625 超合金的微观结构和相关机械性能的影响

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

Materials Science and Engineering: A

Pub Date : 2024-11-14 DOI: 10.1016/j.msea.2024.147551

Ruohan Zhao, Lulu Li, Zhenhua Nie, Zongqing Ma, Qianying Guo

Copper-based alloys possess outstanding thermal and electrical conductivity, making them popular in the electronic and aerospace industries. However, its low hardness makes it vulnerable to failure in harsh service environments, which require surface coating. By using the direct laser metal deposition method to coat harder alloys on the surface of Cu alloys, the challenge of this copper alloy's high laser reflectivity was noted. To solve this problem, both substrate preheating and high-power LMD methods were employed, which established an excellent metallurgical bonding between the coating and substrate with a 2 μm diffusion layer and enhanced the Cu-Cr-Zr substrate's hardness and wear resistance. Due to the presence of copper elements in the fusion zone, the constituent supercooling zone is increased, resulting in a finer columnar crystal structure in the fusion zone. Such elements exchange process during LMD produces will also improve the mechanical properties of the Cu-Cr-Zr substrate by solid solution strengthening.

铜基合金具有出色的导热性和导电性，因此在电子和航空航天工业中很受欢迎。然而，由于硬度较低，在恶劣的使用环境中容易发生故障，因此需要进行表面涂层处理。通过使用直接激光金属沉积法在铜合金表面涂覆硬度更高的合金，人们注意到了这种铜合金的高激光反射率所带来的挑战。为了解决这个问题，我们采用了基底预热和高功率 LMD 两种方法，在涂层和基底之间形成了 2 μm 的扩散层，形成了良好的冶金结合，提高了 Cu-Cr-Zr 基底的硬度和耐磨性。由于熔合区中铜元素的存在，成分过冷区增大，从而使熔合区的柱状晶结构更加精细。LMD 生产过程中的这种元素交换过程还将通过固溶强化来改善 Cu-Cr-Zr 基材的机械性能。

{"title":"Effects of pre-heating induced interfacial diffusion on microstructure and related mechanical properties of direct laser metal deposited Inconel 625 superalloy on a Cu-Cr-Zr substrate","authors":"Ruohan Zhao, Lulu Li, Zhenhua Nie, Zongqing Ma, Qianying Guo","doi":"10.1016/j.msea.2024.147551","DOIUrl":"10.1016/j.msea.2024.147551","url":null,"abstract":"<div><div>Copper-based alloys possess outstanding thermal and electrical conductivity, making them popular in the electronic and aerospace industries. However, its low hardness makes it vulnerable to failure in harsh service environments, which require surface coating. By using the direct laser metal deposition method to coat harder alloys on the surface of Cu alloys, the challenge of this copper alloy's high laser reflectivity was noted. To solve this problem, both substrate preheating and high-power LMD methods were employed, which established an excellent metallurgical bonding between the coating and substrate with a 2 μm diffusion layer and enhanced the Cu-Cr-Zr substrate's hardness and wear resistance. Due to the presence of copper elements in the fusion zone, the constituent supercooling zone is increased, resulting in a finer columnar crystal structure in the fusion zone. Such elements exchange process during LMD produces will also improve the mechanical properties of the Cu-Cr-Zr substrate by solid solution strengthening.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147551"},"PeriodicalIF":6.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663406","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

Strength and ductility of additively manufactured 310 austenitic stainless steel via wire-arc directed energy deposition: The role of columnar grain growth and ductility-dip cracking 通过线弧定向能沉积快速制造的 310 奥氏体不锈钢的强度和延展性：柱状晶粒生长和延展性-浸裂的作用

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

Materials Science and Engineering: A

Pub Date : 2024-11-13 DOI: 10.1016/j.msea.2024.147554

Ali Rahimi , Morteza Yazdizadeh , Masoud Vatan Ara , Majid Pouranvari

This study investigates the underlying factors governing the mechanical properties of single-wall additively manufactured SS 310 austenitic stainless steel via wire-arc directed energy deposition. It demonstrates the predominant microstructural feature in the printed SS 310 stainless steel is the formation of epitaxial large columnar austenite grains, which promotes the occurrence of sub-solidus solid-state ductility-dip cracking (DDC) during the multi-layer additive manufacturing process. While the yield strength and tensile strength of wire-arc additively manufactured SS 310 are comparable to those of wrought annealed AISI 310, the short micro-cracks and the presence of δ-ferrite hinder the work hardening rate and uniform elongation. Additionally, micro-cracks promote void nucleation during the ductile fracture process, resulting in a noteworthy reduction in post-necking elongation and energy absorption capability. The stress-strain behavior of the manufactured part exhibits anisotropy due to the growth of columnar grains, the heterogeneous periodic microstructure, and the orientation of the ductility-dip cracks. To fully harness the potential of wire-arc additive manufacturing as a cost-effective and sustainable manufacturing process, it is imperative to optimize the grain structure and minimize residual stress to eliminate the occurrence of DDC in the production of SS 310 austenitic stainless steel.

本研究探讨了通过线弧定向能沉积法添加剂制造的单壁 SS 310 奥氏体不锈钢机械性能的基本因素。研究表明，印刷 SS 310 不锈钢的主要微观结构特征是形成了外延大柱状奥氏体晶粒，这促进了多层添加制造过程中固相下固态韧性-浸裂（DDC）的发生。虽然线弧添加剂制造的 SS 310 的屈服强度和抗拉强度与锻造退火的 AISI 310 相当，但短微裂纹和 δ 铁素体的存在阻碍了加工硬化率和均匀伸长率。此外，在韧性断裂过程中，微裂纹会促进空洞成核，导致颈后伸长率和能量吸收能力显著降低。由于柱状晶粒的生长、异质周期性微结构以及韧性浸渍裂纹的取向，制件的应力应变行为呈现出各向异性。为了充分发挥线弧快速成型技术作为一种经济高效、可持续发展的制造工艺的潜力，在生产 SS 310 奥氏体不锈钢的过程中，必须优化晶粒结构，尽量减少残余应力，以消除 DDC 的发生。

{"title":"Strength and ductility of additively manufactured 310 austenitic stainless steel via wire-arc directed energy deposition: The role of columnar grain growth and ductility-dip cracking","authors":"Ali Rahimi , Morteza Yazdizadeh , Masoud Vatan Ara , Majid Pouranvari","doi":"10.1016/j.msea.2024.147554","DOIUrl":"10.1016/j.msea.2024.147554","url":null,"abstract":"<div><div>This study investigates the underlying factors governing the mechanical properties of single-wall additively manufactured SS 310 austenitic stainless steel via wire-arc directed energy deposition. It demonstrates the predominant microstructural feature in the printed SS 310 stainless steel is the formation of epitaxial large columnar austenite grains, which promotes the occurrence of sub-solidus solid-state ductility-dip cracking (DDC) during the multi-layer additive manufacturing process. While the yield strength and tensile strength of wire-arc additively manufactured SS 310 are comparable to those of wrought annealed AISI 310, the short micro-cracks and the presence of δ-ferrite hinder the work hardening rate and uniform elongation. Additionally, micro-cracks promote void nucleation during the ductile fracture process, resulting in a noteworthy reduction in post-necking elongation and energy absorption capability. The stress-strain behavior of the manufactured part exhibits anisotropy due to the growth of columnar grains, the heterogeneous periodic microstructure, and the orientation of the ductility-dip cracks. To fully harness the potential of wire-arc additive manufacturing as a cost-effective and sustainable manufacturing process, it is imperative to optimize the grain structure and minimize residual stress to eliminate the occurrence of DDC in the production of SS 310 austenitic stainless steel.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147554"},"PeriodicalIF":6.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663348","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

Effects of TiB2 particles on deformation behavior, softening mechanisms and recrystallization texture of hot-compressed Fe-TiB2 composites TiB2 颗粒对热压 Fe-TiB2 复合材料变形行为、软化机制和再结晶纹理的影响

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

Materials Science and Engineering: A

Pub Date : 2024-11-13 DOI: 10.1016/j.msea.2024.147540

Yujiao Ke , Bin Fu , Chong Peng , Ze Qiao , Kaiyao Wang , Yue Dong , Hu Tang , Zhefeng Xu , Kazuhiro Matsugi

Fe-TiB₂ composites, also termed as high modulus steel, offer a promising solution to the challenge of achieving both lightweight and high stiffness materials. However, the presence of TiB₂ particles in Fe-TiB₂ composites results in poor hot-workability. Therefore, understanding the effects of TiB₂ particles on the hot deformation behavior, dynamic recrystallization (DRX), and microstructural evolution of Fe-TiB₂ composites is crucial for optimizing their hot-working process. In this study, we elucidated the effects of TiB₂ particles on deformation behavior and dynamic softening behavior by conducting a series of isothermal compression tests on as-cast Fe-TiB₂ composites and as-cast base alloys (control group) at temperatures of 800–1200 °C, strains of 0.36–1.2, and strain rates of 0.01–1 s⁻¹. Using electron backscatter diffraction, we characterized the microstructures of composites and base alloys, showing that TiB₂ particles induce a DRX process through particle stimulated nucleation (PSN) at low temperatures and promote continuous dynamic recrystallization (CDRX) at high temperatures. The presence of TiB₂ particles have significantly affected the dislocation movement and distribution, which changes the deformation energy distribution and thus facilitates different DRX behaviors under various thermal deformation conditions. Additionally, the microstructure resulting from DRX through PSN exhibits significant texture weakening and grain refinement, presenting a promising method for fabricating ultrafine-grained Fe-TiB₂ composites.

Fe-TiB2复合材料也被称为高模量钢，它为实现轻质高刚度材料的挑战提供了一种前景广阔的解决方案。然而，Fe-TiB2 复合材料中 TiB2 颗粒的存在导致热加工性能较差。因此，了解 TiB2 颗粒对 Fe-TiB2 复合材料的热变形行为、动态再结晶（DRX）和微结构演变的影响对于优化其热加工工艺至关重要。在本研究中，我们对铸态 Fe-TiB2 复合材料和铸态基合金（对照组）进行了一系列等温压缩试验，在温度为 800-1200 ℃、应变为 0.36-1.2 和应变率为 0.01-1 s-1 的条件下，阐明了 TiB2 颗粒对变形行为和动态软化行为的影响。利用电子反向散射衍射，我们对复合材料和基合金的微观结构进行了表征，结果表明 TiB2 粒子在低温下通过粒子刺激成核（PSN）诱导 DRX 过程，并在高温下促进连续动态再结晶（CDRX）。TiB2 粒子的存在极大地影响了位错的运动和分布，从而改变了形变能量分布，进而促进了各种热形变条件下的不同 DRX 行为。此外，通过 PSN 进行 DRX 所产生的微观结构表现出明显的纹理弱化和晶粒细化，为制造超细晶粒的 Fe-TiB2 复合材料提供了一种可行的方法。

{"title":"Effects of TiB2 particles on deformation behavior, softening mechanisms and recrystallization texture of hot-compressed Fe-TiB2 composites","authors":"Yujiao Ke , Bin Fu , Chong Peng , Ze Qiao , Kaiyao Wang , Yue Dong , Hu Tang , Zhefeng Xu , Kazuhiro Matsugi","doi":"10.1016/j.msea.2024.147540","DOIUrl":"10.1016/j.msea.2024.147540","url":null,"abstract":"<div><div>Fe-TiB<sub>2</sub> composites, also termed as high modulus steel, offer a promising solution to the challenge of achieving both lightweight and high stiffness materials. However, the presence of TiB<sub>2</sub> particles in Fe-TiB<sub>2</sub> composites results in poor hot-workability. Therefore, understanding the effects of TiB<sub>2</sub> particles on the hot deformation behavior, dynamic recrystallization (DRX), and microstructural evolution of Fe-TiB<sub>2</sub> composites is crucial for optimizing their hot-working process. In this study, we elucidated the effects of TiB<sub>2</sub> particles on deformation behavior and dynamic softening behavior by conducting a series of isothermal compression tests on as-cast Fe-TiB<sub>2</sub> composites and as-cast base alloys (control group) at temperatures of 800–1200 °C, strains of 0.36–1.2, and strain rates of 0.01–1 s⁻<sup>1</sup>. Using electron backscatter diffraction, we characterized the microstructures of composites and base alloys, showing that TiB<sub>2</sub> particles induce a DRX process through particle stimulated nucleation (PSN) at low temperatures and promote continuous dynamic recrystallization (CDRX) at high temperatures. The presence of TiB<sub>2</sub> particles have significantly affected the dislocation movement and distribution, which changes the deformation energy distribution and thus facilitates different DRX behaviors under various thermal deformation conditions. Additionally, the microstructure resulting from DRX through PSN exhibits significant texture weakening and grain refinement, presenting a promising method for fabricating ultrafine-grained Fe-TiB<sub>2</sub> composites.</div></div>","PeriodicalId":385,"journal":{"name":"Materials Science and Engineering: A","volume":"920 ","pages":"Article 147540"},"PeriodicalIF":6.1,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663398","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