International Journal of Plasticity最新文献

{"title":"Dual-scale selection of martensite variants in shape memory intermetallic compounds during thermomechanical loading","authors":"Hai-Le Yan ,&nbsp;Ying Zhao ,&nbsp;Yudong Zhang ,&nbsp;Weimin Gan ,&nbsp;Claude Esling ,&nbsp;Xiang Zhao ,&nbsp;Liang Zuo","doi":"10.1016/j.ijplas.2025.104570","DOIUrl":"10.1016/j.ijplas.2025.104570","url":null,"abstract":"<div><div>Generating a pre-strain by mechanical loading during martensitic transformation stands as a crucial strategy to obtain memory effect in shape memory alloys (SMAs). As martensitic transformation is realized by an anisotropic lattice deformation, the formation of martensite variants is always governed by strain accommodation. In a stress-free state, the orientation variants are organized hierarchically into colonies with a fixed number of variants. Under an external load, the transformation becomes selective. Although variant selection has long been a subject of interest, knowledge on selection <em>via</em> the activation of the transformation shear system under a load and by local strain mitigation is limited. Here, by a combined <em>in-situ</em> neutron diffraction and exhaustive EBSD crystallographic examination, the variant selection under a compressive load during martensitic transformation was thoroughly investigated using Ni₅₁Mn₃₄In₁₅ as an example alloy. Remarkably, a dual-scale selection mechanism, <em>i.e.</em>, colony and intra-colony variants, was revealed, which is in stark contrast to the stress-free scenario. For colonies, those containing variants receiving the highest resolved shear stress on their dominant transformation shear system were selected. Within the colonies, the selection is on variant volume fraction. Those making the maximum contribution to the external compression strain were majorly selected. Nevertheless, due to local incompatible strains created by the favorable variants, the variants with deformation opposite to the external compression were also selected to mitigate local incompatible strain and promote further formation of the favorable variants. This study provides useful experimental evidence and analysis data for related crystal plasticity modeling and simulation.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104570"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145608791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical ordering and generalized stacking fault energy in high-entropy alloys: Simulation and multimodal machine learning","authors":"Jianyu Zhang ,&nbsp;Dingqi Zhao ,&nbsp;Junwei Qiao ,&nbsp;Yong-Wei Zhang","doi":"10.1016/j.ijplas.2025.104567","DOIUrl":"10.1016/j.ijplas.2025.104567","url":null,"abstract":"<div><div>Stacking Fault Energy (SFE) is a critical microstructural factor governing deformation mechanisms in high-entropy alloys (HEAs). While traditional computational techniques succeed in understanding SFE, they remain extremely time-consuming. Traditional SFE prediction models, relying solely on composition, cannot describe local atomic clustering effects on SFE. Therefore, developing specialized machine learning (ML)-accelerated methods capable of predicting SFE is crucial for guiding high-performance alloy design.</div><div>Multiple studies have demonstrated that the variables influencing the SFE of alloys are not limited to alloy composition; short-range ordering (SRO) is equally important. This study used MD simulations to investigate the combined influence of composition and SRO in Cr_x(FeCoNi)_1-x HEAs. It was found that after the introduction of SRO, the average SFE increased by 21.2 ± 7.1 mJ/m² (2.7-fold higher than the random solid solution (RSS) state), and the yield strength was significantly enhanced by 3 GPa (1.2-fold higher than the RSS state). This is attributed to Cr clustering around dislocations in the SRO state.</div><div>SRO and alloy composition are simultaneously important influencing factors for SFE, and traditional models that rely on single-variable predictions struggle to capture the coupling effects of these two factors. Therefore, this study maps compositional variables and the degree of ordering into structural features and image information, which serve as concurrent inputs for a neural network, to construct an efficient predictive model via a multimodal machine learning algorithm. This predictive method is 2 orders of magnitude faster than traditional models, providing an efficient tool for HEAs design and microscopic deformation mechanism studies.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104567"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145583583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shock-induced hierarchical plastic deformations in high entropy (Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2)C at high strain rate","authors":"Lanxi Feng ,&nbsp;Wanghui Li ,&nbsp;Wenxuan Tang ,&nbsp;Zhuochen Chen ,&nbsp;Xiaoqing Zhang ,&nbsp;Yilun Xu ,&nbsp;Guglielmo Vastola ,&nbsp;Fu-Zhi Dai ,&nbsp;Yong-Wei Zhang ,&nbsp;Xiaohu Yao","doi":"10.1016/j.ijplas.2025.104543","DOIUrl":"10.1016/j.ijplas.2025.104543","url":null,"abstract":"<div><div>Conventional ceramics have ultra-high strength but often lack plasticity. The high-entropy carbide ceramics (HECCs) offer a new perspective to enhance the plasticity of ceramics, which may extend their applicability as components operating under extreme conditions. However, there still lacks research on the dynamic behavior of HECCs, causing a poor understanding of their plastic response to dynamic loading. In this work, the dynamic behavior of a high-entropy ceramic (Zr_0.2Hf_0.2Ti_0.2Nb_0.2Ta_0.2)C (denoted as HEC) under shock compression is investigated, for the first time, by the plate impact experiments with two-stage gas gun and molecular dynamics simulations utilizing a deep learning potential based on accurate first-principles data. With increasing shock pressure, HEC undergoes a pronounced elastic-plastic transition characterized by the formation of multiple plastic deformation bands, local phase transition and amorphization, which involve the activations of <span><math><mrow><mo>&lt;</mo><mn>1</mn><mspace></mspace><mover><mn>1</mn><mo>¯</mo></mover><mspace></mspace><mn>0</mn><mo>&gt;</mo><mrow><mo>{</mo><mn>1</mn><mspace></mspace><mn>1</mn><mspace></mspace><mn>0</mn><mo>}</mo></mrow></mrow></math></span> and <span><math><mrow><mo>&lt;</mo><mn>1</mn><mspace></mspace><mover><mn>1</mn><mo>¯</mo></mover><mspace></mspace><mn>0</mn><mo>&gt;</mo><mrow><mo>{</mo><mn>1</mn><mspace></mspace><mn>1</mn><mspace></mspace><mn>1</mn><mo>}</mo></mrow></mrow></math></span> slip systems simultaneously. The local lattice distortions in HEC are found to influence the behavior of dislocation propagation during shock compression. Instead of following predefined paths, dislocations tend to deviate at the propagation front, resulting in the formation of vacancies. Our findings reveal the hierarchical plastic deformation mediated by multi-competing mechanisms in HEC under extreme conditions, suggesting a promising strategy for achieving HECCs that are both strong and ductile.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104543"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145441398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dislocation-interface interdependent twinning and sequential kinking deformation in fully lamellar Ti alloys fabricated by additive manufacturing","authors":"Guoqiang Zhu ,&nbsp;Baoxian Su ,&nbsp;Botao Jiang ,&nbsp;Liang Wang ,&nbsp;Yupu Cheng ,&nbsp;Wuxin Fan ,&nbsp;Jiachen Zhou ,&nbsp;Hao Guo ,&nbsp;Chao Xu ,&nbsp;Yanqing Su","doi":"10.1016/j.ijplas.2025.104580","DOIUrl":"10.1016/j.ijplas.2025.104580","url":null,"abstract":"<div><div>With advancements in aerospace, superconducting technology, and advanced propulsion systems, the demand for cryogenic structural materials has become more stringent. Titanium alloys, known for the merits of lightweight and high strength, are promising candidates for such applications. Compared with other microstructural morphologies, the fully lamellar microstructure is recognized for its exceptional cryogenic ductility, which is primarily attributed to the nucleation and propagation of deformation twins. Although the role of α/β interfaces in plastic deformation is widely acknowledged, their potential effects on deformation behavior have yet to be fully elucidated. This work investigates microscale deformation mechanisms, which is associated with interface-mediated deformation modes. The fully lamellar Ti6321 alloy developed from Ti6Al4V is entirely composed of large-scale colonies with periodic arrangement of alternating α and β lamellae. The α/β interface is systematically characterized prior to cryogenic deformation, confirming a perfect Burgers Orientation Relationship (BOR) and misfit dislocations between the initial α and β phases. Post-deformation analysis under cryogenic conditions reveals the presence of {1-102} deformation twins and kinked β lamellae. During cryogenic deformation, twin variants with high Schmid factor (SF) emerge first to facilitate plastic accommodation. Notably, twinning can be also triggered in some low-SF twinned colonies that exhibit intense 〈<em>a〉</em> dislocations, which can be driven by the dissociation of basal 〈<em>a〉</em> dislocations. Crucially, these twins propagate continuously across multiple β lamellae via a β kinking-assisted mechanism, providing an efficient pathway for strain accommodation. The synergistic effect of α twinning and sequential β phase kinking contributes to alleviate stress localization, dissipating stored plastic energy, thereby strengthening the cryogenic strength and ductility for the fully lamellar Ti alloys.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104580"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145730915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth selection of deformation twins in hexagonal titanium","authors":"Bhargav R. Sudhalkar ,&nbsp;Rakesh Kumar Barik ,&nbsp;Anirban Patra ,&nbsp;Komal Kapoor ,&nbsp;Rajeev Kapoor ,&nbsp;Ankit Agrawal ,&nbsp;Indradev Samajdar","doi":"10.1016/j.ijplas.2025.104574","DOIUrl":"10.1016/j.ijplas.2025.104574","url":null,"abstract":"<div><div>A combination of experiments and molecular dynamics (MD) simulations was used to explore deformation twinning in hexagonal titanium. These were <span><math><mrow><mo>{</mo><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>2</mn></mrow><mo>}</mo></mrow></math></span> tensile twins, and their relative area fractions were governed by crystallography. High-resolution microtexture measurements distinguished them as S-type and N-type. S-type involved ‘visible’ slip transfer. In particular, a near-boundary misorientation build-up in the twin-neighbor grain was observed. The N-type twins, in contrast, exhibited no such misorientation development. Collectively, N-type twins grew faster, but a few of them also had comparable growth rates as S-type twins. Mesoscopic differences in twin growth were supported microscopically. Only a few of the grain boundary microscopic deformation twins grew. Further, twin-matrix interfaces exhibited microscopic differences in morphologies and local residual strains. To expand the microstructural observations and to explore associated mechanism(s), focused MD-simulations were conducted. Deformation twins were simulated on bi-crystal models, incorporating differences in twin-neighbor slip transfer. S-type twins occurred at lower stresses and exhibited noticeable relative atomic displacements across twin-neighbor boundaries. This mimicked experimental misorientation build-up. Though nucleation and growth of all deformation twins introduced atomic shuffle, S-type twins were preceded by the formation of stacking faults and atomic shear. Further, the simulated growth of deformation twins was governed by stress-relaxation in the twin-embryo stage and by the accumulation of twin-matrix interfacial dislocations during subsequent twin growth. In summary, this study brought out a novel perspective on <em>growth selection of deformation twinning in hexagonal titanium</em>.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104574"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145657430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ascertaining the plastic deformation mechanisms of polycrystalline extruded Zn through in situ SEM/EBSD mechanical tests","authors":"Alireza Rezaei ,&nbsp;Nafiseh Mollaei ,&nbsp;Maral Sarebanzadeh ,&nbsp;Biaobiao Yang ,&nbsp;Seyed Mahmood Fatemi ,&nbsp;Javier LLorca","doi":"10.1016/j.ijplas.2025.104548","DOIUrl":"10.1016/j.ijplas.2025.104548","url":null,"abstract":"<div><div>The plastic deformation micro-mechanisms of extruded pure Zn deformed in tension along the extrusion direction were investigated by means of <em>in situ</em> scanning electron microscopy (SEM) integrated with electron back-scatter diffraction (EBSD). Plastic deformation began with the activation of 〈<em>a〉</em> basal slip in grains with the highest Schmid factor while, the incompatibility of deformation between neighbour grains was accommodated by grain boundary sliding. The geometrically necessary dislocation density increased sharply from 1.53 × 10¹³ m⁻² to 9.03 × 10¹³ m⁻² when applied strain reached 6.7%, and this increase coincides with the strong initial strain hardening region. The incompatibility of deformation between neighbour grains was accommodated by grain boundary sliding at strains above 3.3%, which somehow limited the strain hardening rate. Evidence of 〈<em>c</em> <em>+</em> <em>a〉</em> pyramidal II slip was also found through slip trace analysis from the early stages of deformation, <em>i.e.</em> 1.6% strain, but it was always limited to a small fraction of suitably oriented grains. Moreover, transmission electron microscopy (TEM) observations showed that many 〈<em>c</em> <em>+</em> <em>a〉</em> pyramidal dislocations were dissociated into the basal plane and became sessile. {<span><math><mrow><mn>10</mn><mover><mrow><mn>1</mn></mrow><mo>‾</mo></mover><mn>2</mn></mrow></math></span>}&lt;<span><math><mrow><mn>10</mn><mover><mrow><mn>1</mn></mrow><mo>‾</mo></mover><mover><mrow><mn>1</mn></mrow><mo>‾</mo></mover></mrow></math></span>&gt; compression twins were nucleated at 3.3% strain and the fraction of grains undergoing twinning as well as the area fraction of twins increased proportionally to the applied strain. Twinning was favoured by the fiber texture and the twin variant with the highest Schmid factor was primarily activated in each grain. The contribution of twinning to the total strain was limited (around 11% when the applied strain was 16.7%). The strain hardening rate decreased sharply beyond 6.7% and the hardening contribution of basal slip was balanced by grain boundary sliding and compression twinning. Finally, a high fraction of sub-grain boundaries that trigger recrystallization at larger strains was found at 16.7%. These observations reveal the sequence and interaction of plastic deformation mechanisms in Zn, which may help design novel Zn alloys with improved mechanical properties.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104548"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145485095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A phase-field model for Mg-NiTi shape memory alloy composites incorporating multiple inelastic deformation mechanisms","authors":"Bo Xu ,&nbsp;Jiachen Hu ,&nbsp;Chao Yu ,&nbsp;Junyuan Xiong ,&nbsp;Di Song ,&nbsp;Chong Wang ,&nbsp;Qianhua Kan ,&nbsp;Qingyuan Wang ,&nbsp;Guozheng Kang","doi":"10.1016/j.ijplas.2025.104555","DOIUrl":"10.1016/j.ijplas.2025.104555","url":null,"abstract":"<div><div>A crystal plasticity-based phase-field model that comprehensively accounts for the inelastic deformation mechanisms of both magnesium (Mg) and NiTi shape memory alloys is proposed to describe the inelastic deformation of Mg-NiTi composites. The thermodynamic driving forces governing the inelastic deformation mechanisms are strictly derived under the framework of irreversible thermodynamics. The compressive deformation behaviors of Mg-NiTi composites with various volume fractions of superelastic and shape-memory NiTi reinforcements are simulated. The validity of the proposed phase-field model is confirmed by qualitatively comparing the experimental results with the simulated ones. The results indicate that during compression, the Mg-NiTi composites exhibit distinct deformation mechanisms depending on the reinforcement type and content. For the composites with a low superelastic NiTi content, inelastic deformation occurs through the twinning and dislocation slip of Mg phase. With a higher superelastic NiTi content, the plastic deformation of the composites is first dominated by the twinning and dislocation slip of Mg phase, followed by the martensite transformation of NiTi phase. In the shape-memory NiTi-reinforced composites, low reinforcement fractions lead to a plastic deformation dominated by the twinning and dislocation slip of Mg phase with a supplementary martensite reorientation of NiTi phase. At higher shape-memory NiTi fractions, the plastic deformation involves coordinated contributions from both phases, i.e., the twinning and dislocation slip in Mg phase, as well as the martensite reorientation and plasticity in NiTi phase. The proposed phase-field model offers a theoretical framework for simulating the microstructure-dependent mechanical behavior of Mg-NiTi composites with arbitrary phase volume fractions and morphologies, which can assist the design of high-performance Mg-NiTi composites with tunable mechanical properties through microstructure engineering, such as phase morphology optimization and texture engineering.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104555"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145553364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of length scale on strengthening and toughening mechanism of Cr-rich precipitates in multi-principal element alloy","authors":"Weiming Huang ,&nbsp;Shuai Shen ,&nbsp;Xingliang Pu ,&nbsp;Shuaikang Zhou ,&nbsp;Xiaoxiao Wang ,&nbsp;Qi Xu ,&nbsp;Siyu Liu ,&nbsp;Zhanghua Gan ,&nbsp;Chuandong Wu ,&nbsp;Jing Liu","doi":"10.1016/j.ijplas.2025.104578","DOIUrl":"10.1016/j.ijplas.2025.104578","url":null,"abstract":"<div><div>Cr is essential for enhancing corrosion and oxidation resistance in advanced metallic systems. However, high Cr content may promote the formation of coarse Cr-rich phases (e.g. σ phase), which significantly deteriorate the mechanical performance. Currently, a type of nano-sized Cr-rich precipitates was detected with homogeneous distribution and coherent structure in multi-principal element alloys (MPEAs). It was revealed that the carbon addition can promote the precipitation of the σ phase. Besides, metastable coherent Cr-rich phases were precipitated during the annealing process with the size less than 5 nm. Noted that the tensile strength of MPEAs is 1189.6 MPa at 25 °C and 560.0 MPa at 700 °C, benefiting from both precipitation enhancement and coherent interfaces. This unconventional coherent interface originates from the structural instability of the metastable coherent Cr-rich nanoprecipitates. Metastable coherent Cr-rich nanoprecipitates formed during short-term annealing are coherent with the FCC matrix but will transform into stable non-coherent σ phase after long-term thermal exposure. Dislocations can directly shear the coherent Cr-rich nanoprecipitates, thereby contributing to the synergy of its strength and ductility. These findings provide new insights into the design and application of high-Cr multi-component alloys.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104578"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145703928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Achieving ultra-high twin density and strength in HCP materials with selectively activated twining systems","authors":"Zhaowen Huang ,&nbsp;Shuaizhuo Wang ,&nbsp;Haotian Yan ,&nbsp;Donghui Wen ,&nbsp;Na Lin ,&nbsp;Zhicheng Miao ,&nbsp;Xiaodong Hou ,&nbsp;Anding Wang ,&nbsp;Yusheng Li ,&nbsp;Yang Cao ,&nbsp;Biao Wang","doi":"10.1016/j.ijplas.2025.104552","DOIUrl":"10.1016/j.ijplas.2025.104552","url":null,"abstract":"<div><div>Twinning is a highly effective mechanism for enhancing the mechanical properties of hexagonal close-packed (HCP) materials. However, achieving ultra-high twin density in a scalable, time- and energy-efficient manner remains a significant challenge. In this study, the combined influence of deformation temperature and crystallographic texture on twinning system selection in commercially pure Ti were systematically investigated. Through tailored texture modification and cryogenic rolling, a high-density twin (HDT) structure with a twin volume fraction exceeds 67% was successfully fabricated. These twinning activities promoted the generation of unfavoured &lt;<em>a</em>&gt;-basal, &lt;<em>c</em>&gt;-prismatic and 〈<em>c</em> + <em>a〉</em> pyramidal slips. The resulting HDT-Ti exhibited an ultrahigh yield strength above 950 MPa and an ultimate tensile strength around 1 GPa. This superior performance arises from multiple strengthening mechanisms, including twinning, dislocation accumulation, and grain boundary effects. Notably, the activation of twinning systems exhibited unexpected dependencies on temperature and texture: extension twins, characterized by lower twinning shear, predominated at room temperature irrespective of orientation; while compression twins, which have higher twinning shear, were significantly activated only under cryogenic conditions even in the unfavourably oriented grain. These unconventional behaviours were elucidated through electron backscatter diffraction analysis, twinning shear calculations, and atomic shuffling considerations. The findings offer new insights into twinning system selection and provide a practical, scalable route to design bulk HCP materials with tailored twin architectures and superior strength-ductility synergy.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104552"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145545449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Twinning- and transformation-induced high cryogenic strength and ductility of the CoCrFeNi high-entropy alloy: Experiment and MD simulation","authors":"Yuze Wu ,&nbsp;Zhide Li ,&nbsp;Charlie Kong ,&nbsp;M.W. Fu ,&nbsp;Hailiang Yu","doi":"10.1016/j.ijplas.2025.104553","DOIUrl":"10.1016/j.ijplas.2025.104553","url":null,"abstract":"<div><div>The CoCrFeNi high-entropy alloy (HEA) processed by asymmetric cryorolling (ACR) followed by short-term annealing exhibited an exceptional strength-ductility synergy under cryogenic conditions. Compared to room temperature, the tensile strength increased from 880 to 1281 MPa, and the fracture elongation increased from 50.1 % to 89.8 %. To reveal the underlying mechanism, molecular dynamics (MD) simulations were employed to investigate the deformation processes at room and cryogenic temperatures. The simulations revealed distinct microstructural evolution pathways involving intrinsic stacking faults (ISFs), extrinsic stacking faults (ESFs), twins, and HCP phases. The combined experimental and simulation results demonstrate that twinning and HCP-phase formation are the dominant deformation mechanisms responsible for the enhanced strength and ductility at cryogenic temperatures. Under cryogenic conditions, twinning and HCP-phase formation initiated at lower strain levels. Compared with tensile deformation at room temperature, the higher flow stress and the cryogenic environment during cryogenic tensile deformation led to denser twin systems, more extensive Lomer-Cottrell (L–C) lock networks, and greater HCP-phase formation, resulting in exceptional strain-hardening capacity and ultrahigh ductility. These findings provide a comprehensive understanding of the microstructural evolution and strengthening mechanisms in HEAs under extreme conditions, offering a promising processing route for producing materials for aerospace applications with high strength and ductility.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"196 ","pages":"Article 104553"},"PeriodicalIF":12.8,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145553362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}