International Journal of Plasticity最新文献

{"title":"Fast Fourier transform approach to Strain Gradient Crystal Plasticity: Regularization of strain localization and size effect","authors":"Amirhossein Lame Jouybari ,&nbsp;Samir El Shawish ,&nbsp;Leon Cizelj","doi":"10.1016/j.ijplas.2024.104153","DOIUrl":"10.1016/j.ijplas.2024.104153","url":null,"abstract":"<div><div>The Strain Gradient Crystal Plasticity (SGCP) model, based on cumulative shear strain, is developed to regularize and simulate the size effect behavior of polycrystalline aggregates, specifically addressing the formation of localization bands, such as slip and kink bands, influenced by strain softening during the initial stages of plastic deformation. In this respect, the thermodynamically consistent derivation of the SGCP equations is presented, establishing their connection to the kinematics of classical crystal plasticity (CCP) framework. The governing balance equations are solved using the fixed-point algorithm of the fast Fourier transform (FFT)-homogenization method, involving explicit coupling between the classical and SGCP balance equations. To address this problem, a strong 21-voxel finite difference scheme is established. This scheme is considered to solve the higher order balance equation inherent to SGCP. Additionally, three types of interface conditions are implemented to explore the impact of grain boundaries on the transmission of localization bands. These conditions yield consistent intragranular/transgranular localization patterns in the MicroFree and MicroContinuity cases, while in the MicroHard condition all localization bands are intragranular with stress concentrations appearing at the grain boundaries.</div><div>Analytical solutions corresponding to different material behaviors are developed and compared with numerical results to validate the numerical implementation of the FFT fixed-point algorithm. It is observed that both the macroscopic behavior and microscopic variables in CCP framework are highly influenced by grid resolutions (non-objective), leading to numerical instabilities arising from the material softening and subsequent formation of localization bands, both in single crystals and polycrystalline aggregates. Remarkably, the developed SGCP model provides results that are independent of grid resolutions (objective) and effectively regularizes the material behavior on local scale. Moreover, the non-local parameter of the model is capable of controlling the localization band widths. Finally, the proposed SGCP model, together with employed MicroHard condition on grain boundaries, is demonstrated to qualitatively reproduce main microstructural features of irradiated polycrystalline materials.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104153"},"PeriodicalIF":9.4,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142541511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic strain ageing of L12-strengthened Ni-Co base high-entropy alloy and unraveling its deformation mechanisms in strain ageing process","authors":"Jinxiong Hou ,&nbsp;Jie Gan ,&nbsp;Tao Wang ,&nbsp;Jianchao Han ,&nbsp;Zhongkai Ren ,&nbsp;Zhihua Wang ,&nbsp;Junwei Qiao ,&nbsp;Yong Zhang ,&nbsp;Tao Yang","doi":"10.1016/j.ijplas.2024.104151","DOIUrl":"10.1016/j.ijplas.2024.104151","url":null,"abstract":"<div><div>Dynamic strain ageing (DSA) of L1₂-strengthened Ni-Co base high-entropy alloy (HEA) was examined at temperatures varying from 20 to 600 °C with strain rates between 10^–² to 10^–4 s^-1. In normal DSA regimes, elevating temperature or lowering strain rate advances the DSA behavior, resulting in the lowered critical strain and raised amplitude of serrations. Based on strain-rate jump tests, the negative strain-rate sensitivity induced by DSA was observed at the elevated temperature regime, and high apparent activation volumes ranging from 97<span><math><mspace></mspace></math></span>∼ 737<span><math><msup><mi>b</mi><mn>3</mn></msup></math></span> correspond to the strong obstacles effect from the precipitates and the additional pinning strengthening of solute atoms. Transmission electron microscopy evidence suggests that stacking faults prevailed at all testing temperatures, while the serration changes are the outcomes of their dynamic interactions with precipitates and condensed Cr, Co-rich solute cloud. Subsequently, in normal DSA regimes, activation energies required for the onset of type A, a mixture of type A and type A + C, and a mixture of type <em>A</em> + <em>B</em> and type C serrations are 30.6, 65.8, and 101.1 kJ/mol determined by strain ageing model at strain rates of 10^–2, 10^–3, and 10^–4 s^-1, respectively. Lastly, a two-time parameter-based Cottrell-Bilby strain aging kinetic model that considers the solute-dislocation interaction in a pipe diffusion manner is applied to evaluate the DSA strengthening concerning strain, strain rate, and temperature.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104151"},"PeriodicalIF":9.4,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519712","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":"Heterogeneous phase deformation in a dual-phase tungsten alloy mediated by the tungsten/matrix interface: Insights from compression experiments and crystal plasticity modeling","authors":"Zuosheng Li ,&nbsp;Lei Zhang ,&nbsp;Bob Svendsen ,&nbsp;Quanyi Xue ,&nbsp;Sai Tang ,&nbsp;Yunzhu Ma ,&nbsp;Wensheng Liu","doi":"10.1016/j.ijplas.2024.104156","DOIUrl":"10.1016/j.ijplas.2024.104156","url":null,"abstract":"<div><div>Tungsten heavy alloy (WHA) is a typical multiphase alloy material consisting of hard tungsten (W) and soft matrix (γ) phases. When loaded, the two phases deform quite differently due to the large difference in their mechanical properties. At present, our understanding of phase deformation and behavior in the multiphase context is relatively poor compared to the single phase case. Such insight is necessary, however, for the design of multiphase alloys having optimal phase microstructure and corresponding material behavior. By combining mechanical testing and crystal plasticity modeling, the relationship between phase microstructure and multiphase alloy deformation behavior is systematically investigated in this work. The results demonstrate that deformation in the W and γ phases is quite different and related to the contrast in material properties between the two phases. Deformation heterogeneity in the multiphase alloy is characterized by the strain gradient near/across the W/γ interface and differences in phase deformation states in relation to the contrast in phase material properties and phase volume fraction. It is found that dislocation pile-up and twinning are the main mechanisms mediating heterogeneous deformation in the region around W/γ interfaces. Based on this insight, a novel design strategy for multiphase alloys is proposed based on optimization of the contrast in phase mechanical properties and the phase volume fractions. This strategy can be employed to design new tungsten alloys and other multi-phase alloys.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104156"},"PeriodicalIF":9.4,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142536402","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 generalized, computationally versatile plasticity model framework - Part II: Theory and verification focusing on shear anisotropy","authors":"Yong Hou ,&nbsp;Junying Min ,&nbsp;Hyung-Rim Lee ,&nbsp;Jinjin Ha ,&nbsp;Namsu Park ,&nbsp;Myoung-Gyu Lee","doi":"10.1016/j.ijplas.2024.104158","DOIUrl":"10.1016/j.ijplas.2024.104158","url":null,"abstract":"<div><div>Shear-dominated deformation (SHDD) is pivotal in sheet metal forming; however, comprehensive modeling of plastic anisotropy in SHDD, specifically shear anisotropy considering both yield stress and plastic flow, has been inadequately addressed in existing literature. In this work, a generalized constitutive framework is introduced on the basis of stress triaxiality-dependent state variable to accurately emulate plastic anisotropy and the physics-based shear constraint in SHDD. The framework is capable to seamlessly integrate with existing yield criteria, preserving computational efficiency and versatility. Notably, the yield function, anisotropic parameters, and their optimization or analytical determination for the non-shear deformation state remain unaltered. When integrated with the Hill48 yield function, featuring either one or two anisotropic parameters within the generalized constitutive framework, precise characterization of yield strength and plastic flow in SHDD is achieved. The applicability of the framework extends to various anisotropic yield functions such as the widely employed Yld2k-2d and the sixth-order polynomial (Poly6) function as a class of associated flow rule-based yield functions, and one non-quadratic yield function for non-associated flow rule scenarios. Experimental validation with two engineering sheet metals, high-strength dual-phase steel DP980 and high-strength aluminum alloy AA7075-T6, was conducted. Comparative analyses with several recently proposed yield criteria, especially Poly6–18p, highlighted the efficiency of the proposed constitutive framework. Furthermore, this study explores intrinsic shear constraints, particularly the absence of through-thickness strains under in-plane shear stress. Additionally, it offers an enhanced description of plastic anisotropy in shear yield stress within the general framework, providing valuable insights into the complexities of SHDD.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104158"},"PeriodicalIF":9.4,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atomistic simulation of chemical short-range order on the irradiation resistance of HfNbTaTiZr high entropy alloy","authors":"Yang Mo ,&nbsp;Yanxiang Liang ,&nbsp;Wei Guo ,&nbsp;Yiming Tian ,&nbsp;Qiang Wan","doi":"10.1016/j.ijplas.2024.104155","DOIUrl":"10.1016/j.ijplas.2024.104155","url":null,"abstract":"<div><div>High entropy alloys (HEAs) have been considered as one of the potential structural material candidates for fourth-generation nuclear reactors and fusion reactors due to their excellent irradiation resistance. Current studies have shown that the chemical short-range order (CSRO) usually exists in HEAs, which has a significant effect on the mechanical properties and irradiation resistance of HEAs. Refractory high entropy alloys (RHEAs), as a new class of HEAs have better mechanical properties at high temperatures than face-centered cubic (FCC) HEAs, and therefore have better prospects of application in the nuclear field. In this study, CSRO and its effect on the irradiation resistance of HfNbTaTiZr are analyzed via molecular dynamics (MD) and Monte Carlo (MC). The primary cascade simulations, multi-cascade simulations and surface bombardment simulations are carried out to simulate the generation and accumulation of irradiation damage. The results of the primary cascade simulations and surface bombardment simulations of CSRO models show that the presence of CSRO induces cascade splitting into subcascades. The presence of subcascades reduces the thermal peak enhancement effect and thus lowers the recombination rate of Frenkel pairs (FPs) in the damage zone when FPs concentrations are low. However, the creation of subcascades increases the size of the damage zone caused by the cascade. Thus, when the concentrations of FPs are high, the larger area of damage zone allows more of the already existing FPs to be included, thus promoting their recombination, i.e., impedes their accumulation when concentrations are high. These subcascades lower the recombination of FPs at low FPs concentrations but inhibit their accumulation at high FPs concentrations. The presence of CSRO is also beneficial in inhibiting the growth of point defect clusters, which further improves the resistance of HfNbTaTiZr to dislocation generation. Furthermore, the presence of CSRO facilitates the irradiation-induced phase transition. But it is found that HfNbTaTiZr shows suppression of hexagonal close-packed (HCP) cluster growth. And the tendency to break down large HCP clusters into smaller ones is demonstrated in the CSRO model. From our calculations we also find that the irradiation-induced HCP atoms have a higher potential energy relative to the matrix. The potential energy difference between those energetic HCP atoms and the matrix can lead to generating a great number of insurmountable barriers pervading the matrix and largely suppressing the long-term mobility of FPs, thus limiting their aggregation and growth into clusters.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104155"},"PeriodicalIF":9.4,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488123","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":"Stress-induced failure transition in metallic glasses","authors":"Lingyi Meng ,&nbsp;Yuxin Zhang ,&nbsp;Xiaochang Tang ,&nbsp;Xiaohu Yao","doi":"10.1016/j.ijplas.2024.104152","DOIUrl":"10.1016/j.ijplas.2024.104152","url":null,"abstract":"<div><div>As a novel and highly promising metal in the future application of weapons equipment and aerospace fields, metallic glasses (MGs) demonstrate intricate failure modes that encompass both the brittle and plastic characteristics when subjected to varying loading conditions. In this work, a set of Cu₅₀Zr₅₀ models subjected to a combined pure shear and equi-triaxial tension loading are simulated via molecular dynamics to investigate the impact of the stress state on the complex failure modes of MGs. The characteristic and critical moments when failure occurs are established under both the shear-band-induced shear failure and the micro-void-induced tensile fracture. The stress triaxiality is applied as a pivotal stress parameter that governs the transition from the shear failure mode to the tensile failure mode. The critical stress triaxiality of Cu₅₀Zr₅₀ MG is approximately in the range of (2.0, 3.0) when both the shear and tension failures simultaneously occur, resulting in the largest failure strain at various stress states. We subsequently obtain a nearly elliptical yield surface of the Cu₅₀Zr₅₀ MGs, in which the shear failure zone, tensile failure zone, and transition zone are clearly distinguished. The microstructural evolution of MGs during the failure transition is analyzed from the perspective of the specific short-range order. In contrast to the tensile deformation, icosahedral (quasi-icosahedral) clusters demonstrate a high level of shear resistance and remain stable in the shear-dominant deformations, which is confirmed as the structural origin of the stress state impacting the failure transition.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104152"},"PeriodicalIF":9.4,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488926","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":"Structural softening mediated shear bands in high entropy alloys","authors":"Tian-Wei Liu ,&nbsp;Zhuo Pu ,&nbsp;Zeng-Yu Yang ,&nbsp;Xu-Ping Zhang ,&nbsp;Gui-Ji Wang ,&nbsp;Tong Li ,&nbsp;Fu-Hua Cao ,&nbsp;Shi-Teng Zhao ,&nbsp;Yan Chen ,&nbsp;Jian Wang ,&nbsp;Lan-Hong Dai","doi":"10.1016/j.ijplas.2024.104154","DOIUrl":"10.1016/j.ijplas.2024.104154","url":null,"abstract":"<div><div>Plastic flow localization is a fundamental and ubiquitous non-equilibrium phenomenon in metallic materials. Despite decades of extensive study, what derives its emergence remains elusive. Here, we tackle this problem in face-centered cubic (fcc) Cantor alloy by the newly developed ramp wave compression technique, which provides a unique quasi-isentropic loading path. By detailed microstructure characterizations, analytical estimation of temperature increment and large-scale atomistic simulations, we conclude that thermal softening is not a dominant driving force for shear band nucleation. Instead, nanotwinning triggers the initial transformation softening which is then accompanied with severe chemical fluctuations and the creation of low-angle dislocation boundaries (LADBs) associated with enhanced local dislocation slips in the adjacent regions. Such LADBs in turn lead to directional softening, acting as the catalytic mediating distortion between neighboring nanotwins. The interconnection between nanotwins and LADBs is thus regarded as structural origin of shear bands, whereas dynamic recrystallization only occurs later during shear band evolution, accelerating strain localization and thickening shear band. These findings shed new lights into fundamental understanding of shear banding and dynamic failure mechanisms in metallic materials.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104154"},"PeriodicalIF":9.4,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451521","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":"Modified crystal plasticity constitutive model considering tensorial properties of microstructural evolution and creep life prediction model for Ni-based single crystal superalloy with film cooling hole","authors":"Ping Wang ,&nbsp;Zhixun Wen ,&nbsp;Meng Li ,&nbsp;Guangxian Lu ,&nbsp;Hao Cheng ,&nbsp;Pengfei He ,&nbsp;Zhufeng Yue","doi":"10.1016/j.ijplas.2024.104150","DOIUrl":"10.1016/j.ijplas.2024.104150","url":null,"abstract":"<div><div>Accurate assessment of the creep life of film cooling hole structures is critical for long-life design and safe operation of aero engines and gas turbines. Firstly, through the high temperature creep experiment of nickel-based single crystal superalloy with film cooling hole, the microstructure evolution process under multiaxial stress state around film hole is characterized. Then, considering the directional effect of rafting structure and the influence of multiaxial stress, a fourth-order tensor is used to describe the evolution of γ phase width, and the microstructure evolution model accounting for multi-axial stress states is established. The microstructure evolution is coupled into the crystal plasticity constitutive model by Orowan stress. Meanwhile, based on continuous damage mechanics, a new multiaxial damage evolution law is established by introducing a multiaxial ductility factor into the constitutive model. The improved crystal plasticity constitutive model can effectively predict the microstructural evolution under multiaxial stress conditions. Furthermore, the combination of the modified crystal plasticity constitutive model and the critical distance method considering stress gradients is used for life prediction of film cooling hole structures. The prediction results show the effectiveness and necessity of considering the microstructure evolution in the life prediction.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104150"},"PeriodicalIF":9.4,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142436130","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":"3D strain heterogeneity and fracture studied by X-ray tomography and crystal plasticity in an aluminium alloy","authors":"Maryse Gille, Henry Proudhon, Jette Oddershede, Romain Quey, Thilo F. Morgeneyer","doi":"10.1016/j.ijplas.2024.104146","DOIUrl":"https://doi.org/10.1016/j.ijplas.2024.104146","url":null,"abstract":"Strong correlations between measured strain fields and crystal plasticity finite element (CP-FE) predictions based on the real microstructure are found for a plane strain tensile specimen made of 6016 T4 aluminium alloy. This is achieved using multimodal X-ray lab tomography giving access to both the initial grain structure and the strain evolution. The real microstructure of the central region of interest (ROI) of the undeformed specimen is obtained non destructively using lab-based diffraction contrast tomography (DCT) and meshing. An <em>in situ</em> tensile test, using absorption contrast tomography (ACT) is then performed for twelve loading increments up to fracture. Taking advantage of the plane strain condition, the evolution of the internal strain field is measured by two-dimensional digital image correlation (DIC) in the material bulk using the natural speckle provided by intermetallic particles. Early strain heterogeneities in the form of slanted bands, that are spatially stable over time, are revealed and the fracture path – determined from the <em>post mortem</em> scan – is found to coincide with the bands exhibiting maximum strain. CP-FE simulations are performed on the meshed microstructure of the specimen acquired by DCT and are compared with image correlation measurements. The measured strain fields are well described by 3D CP-FE predictions, whilst it is shown that neither a macroscopic anisotropic plasticity model nor a CP-FE simulation with random grain orientations could reproduce the measurements.","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"56 1","pages":""},"PeriodicalIF":9.8,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415544","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":"Enhancing the ductility and yield strength of 2.7Mn steel via two-step partitioning heat treatment","authors":"Wenlu Yu ,&nbsp;Lihe Qian ,&nbsp;Chaozhang Wei ,&nbsp;Kaifang Li ,&nbsp;Yipeng Ding ,&nbsp;Pengfei Yu ,&nbsp;Zhixuan Jia ,&nbsp;Fucheng Zhang ,&nbsp;Jiangying Meng","doi":"10.1016/j.ijplas.2024.104148","DOIUrl":"10.1016/j.ijplas.2024.104148","url":null,"abstract":"<div><div>Fresh martensite (FM) is often present in medium-Mn steels, especially when containing lower Mn content, due to the insufficient thermal stability of reverted austenite; this FM is brittle, largely deteriorating the ductility. In this paper, large ductility and high yield strength are achieved in an Al/Si-added medium-Mn steel containing 2.7Mn via a two-step partitioning heat treatment, i.e. intercritical annealing (IA) followed by low-temperature partitioning (LTP). We show that, during the IA, C and Mn atoms partition from the pre-quenched martensite to reverted austenite; Al addition reduces the size of reverted austenite and promotes C and Mn enrichment in the reverted austenite by decelerating its growth kinetics. This enables the reverted austenite more thermally stabilized, thereby reducing the amount of FM and increasing the amount and mechanical stability of retained austenite (RA) at room temperature. During the LTP, accompanied with the recovery of dislocations and the suppression of carbide precipitation by Al and Si, C atoms further partition from FM to RA, which enables the RA more mechanically stabilized and thereby sustains the high strain hardening to larger strains. Simultaneously, the FM becomes less hard and less brittle due to C atoms depletion and dislocations recovery, alleviating the stress/strain localization and favoring the uniform plastic deformation. Furthermore, the decrease in mobile dislocation density that is accompanied with the recovery of dislocations is believed to be mainly responsible for the enhanced yield strength of the steel. The present results indicate that the synergetic effects of the primary element partitioning (promoted by Al) during IA, which increases the thermal stability of reverted austenite, and the secondary element partitioning (enhanced by Al and Si) and as well dislocation recovery during LTP, which increases the mechanical stability of RA and the uniformity of plastic deformation, significantly enhance both the ductility and yield strength of medium-Mn steel with low Mn content.</div></div>","PeriodicalId":340,"journal":{"name":"International Journal of Plasticity","volume":"183 ","pages":"Article 104148"},"PeriodicalIF":9.4,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142398112","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}