Materials Characterization最新文献

{"title":"Tuning strength and ductility of an Al-4.9 Mg-1.6Li-0.4Cu-0.3Sc-0.2Zr alloy via deep cold rolling and ageing treatment","authors":"Zepeng Zha ,&nbsp;Zhenqiang Wang ,&nbsp;Yunpeng Cheng ,&nbsp;Wenyuan Wang ,&nbsp;Chunhong Zhang","doi":"10.1016/j.matchar.2025.115087","DOIUrl":"10.1016/j.matchar.2025.115087","url":null,"abstract":"<div><div>The microstructural evolution, precipitation behavior, and mechanical properties of an Al-4.9 Mg-1.6Li-0.4Cu-0.3Sc-0.2Zr alloy, produced by deep cold rolling followed by ageing, were examined. As the ageing temperature increases from 95 °C to 165 °C, the peak ageing time of the alloy shortens, and the peak hardness decreases. A heterogeneous structure was observed at 130 °C or higher due to incomplete recrystallization. The homogeneously precipitated Al₃Li (δ′) phase increase in size, but decrease in number density with increasing ageing temperature. The prominent precipitation strengthening resulting from δ′ phases leads to the highest strength (YS = 520 MPa, UTS = 582 MPa) observed at peak-ageing of 95 °C, whereas the alloy of peak-ageing at 165 °C showed the highest ductility (EL = 13.1 %) due to the heterogeneous structure. At 130 °C, a superior combination of strength (YS = 440 MPa, UTS = 530 MPa) and ductility (EL = 8.8 %) is achieved, which are the highest values among the Al-Mg-Li alloy families at present. The study provides a novel strategy to enhance the comprehensive mechanical properties of Al-Mg-Li alloys.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115087"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887265","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}

{"title":"Evolution in microstructure and tensile properties of a novel Al-Mg-Si-Cu alloy under peak-aged condition during fatigue process","authors":"Ni Tian ,&nbsp;Peihong Zhang ,&nbsp;Tianxiang Zhang ,&nbsp;Yinzhu Li ,&nbsp;Yaozhong Zhang ,&nbsp;Yiran Zhou ,&nbsp;Quanxin Yan ,&nbsp;Gang Zhao ,&nbsp;Gaowu Qin","doi":"10.1016/j.matchar.2025.115086","DOIUrl":"10.1016/j.matchar.2025.115086","url":null,"abstract":"<div><div>With the development of high-speed trains towards higher speeds (400 km/h and above) and longer service life, the fatigue performance of its body materials has become a critical factor limiting their safety performance. Therefore, the second-phase particles, grains, dislocations, strength, and elongation of peak-aged Al-0.81Mg-0.84Si-0.53Cu alloy sheets for the body of next-generation high-speed trains were investigated after fatigue loading at 28 MPa/280 MPa for 5 × 10³, 1 × 10⁴, 5 × 10⁴, 1 × 10⁵, and 1.3 × 10⁵ cycles. There were no obvious changes in the second-phase particles and grains of the alloy sheet; however, the dislocation density increased monotonically, and the distribution of dislocations varied with an increase in the number of fatigue cycles. The relationship between the mechanical properties of the alloy sheet and fatigue cycles was characterized by four stages: fatigue hardening stage (&lt;5 × 10³ cycles), fatigue turbulent stage (5 × 10³ cycles to 1 × 10⁴ cycles), fatigue stable stage (1 × 10⁴ cycles to 1 × 10⁵ cycles), and fatigue and buckling stage (1 × 10⁵ to 1.3 × 10⁵ cycles). The results can provide basic data and a theoretical basis for objectively predicting the safe service life of Al-0.81Mg-0.84Si-0.53Cu alloy for high-speed trains.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115086"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881347","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}

{"title":"Additive friction stir deposition of a Ti-6Al-4 V alloy: Microstructure and texture","authors":"Hossein Beladi ,&nbsp;Vahid Tari ,&nbsp;Matthew R. Barnett","doi":"10.1016/j.matchar.2025.115081","DOIUrl":"10.1016/j.matchar.2025.115081","url":null,"abstract":"<div><div>The microstructure and crystallographic texture of a Ti-6Al-4 V alloy produced through additive friction stir deposition were thoroughly investigated in the current study. The deposition was largely performed above the β transus temperature (T_β), leading to β parent grain refinement, which subsequently transformed to fine colonies of α + β lamellar structure following the Burgers orientation relationship upon cooling. The α overall texture exhibited multiple components, closely inherited from the parent β phase subjected to severe shear deformation during deposition above T_β. The deformation of β led to the variant selection during subsequent phase transformation upon cooling, promoting V₁, V₇ and V₄ variants. The variant selection persisted throughout the process, though each deposition layer experienced multiple transformation cycles through subsequent depositions, due to the texture memory effect. This enhanced the population of 60°/<span><math><mfenced><mrow><mn>11</mn><mover><mn>2</mn><mo>¯</mo></mover><mn>0</mn></mrow></mfenced></math></span> and 63.3°/<span><math><mfenced><mrow><mover><mn>10</mn><mo>¯</mo></mover><mspace></mspace><mn>5</mn><mspace></mspace><mn>5</mn><mspace></mspace><mover><mn>3</mn><mo>¯</mo></mover></mrow></mfenced></math></span> boundaries at the expense of other α intervariant boundaries. The distribution of α boundary plane was strongly anisotropic, mostly terminated on the prismatic plane orientations (i.e., <span><math><mfenced><mrow><mi>hki</mi><mn>0</mn></mrow></mfenced></math></span>, ranging from <span><math><mfenced><mrow><mn>4</mn><mover><mn>1</mn><mo>¯</mo></mover><mover><mn>3</mn><mo>¯</mo></mover><mn>0</mn></mrow></mfenced></math></span> and <span><math><mfenced><mrow><mn>5</mn><mover><mn>2</mn><mo>¯</mo></mover><mover><mn>3</mn><mo>¯</mo></mover><mn>0</mn></mrow></mfenced></math></span>). This was due to the constraints associated with the phase transformation crystallography rather than low energy arrangement. The high temperature parent β grain boundaries largely terminated at {111} plane orientation, rather than low energy {110} close packed plane, due to the promotion of 〈111〉 fibre in β overall texture. This restricted the nucleation of grain boundary α having Burgers OR with either side of parent β boundaries. This ultimately led to the simultaneous enhancement in the ductility (∼ 18 % total elongation) and strength (∼ 1040 UTS) of material along both hatch and building directions.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115081"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891875","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}

{"title":"Investigation on microstructural and texture evolution in additive friction stir deposited Inconel 718 alloy","authors":"Tej Prakash,&nbsp;Ranjit Bauri","doi":"10.1016/j.matchar.2025.115088","DOIUrl":"10.1016/j.matchar.2025.115088","url":null,"abstract":"<div><div>Friction stir-based additive manufacturing has shown promising results and has the full potential to fabricate near-net-shaped 3D metallic structures. Most existing research has focused on discontinuous multilayer deposition of nickel-based superalloys using friction surfacing (FS). In this study, a semi-automatic friction stir welding machine operating in vertical position control mode was used to continuously build up multiple layers of Inconel 718 alloy. The process parameters were optimized based on the single-layer deposition of Inconel 718 alloy with different parameter combinations (rotational speed, axial feed, and traverse speed), which resulted in uniform microstructure and hardness. At high axial feed, changes in process path direction in the multilayer process resulted in variations in the axial force and temperature during deposition. Electron back-scattered diffraction (EBSD) analysis revealed the occurrence of discontinuous dynamic recrystallization (DDRX), which led to refined grains during multilayer deposition. Among the evaluated axial feeds (10, 13, and 16 mm/min), 16 mm/min yielded defect-free deposition with optimal microstructure and hardness. Microstructure analysis also revealed banded structures with variations in the grain size, resulting in hardness variation across the layers. The high axial feed showed less variation in grain size in all layers, while few coarser grains were observed at the maximum axial load. The microtexture analysis revealed that at 13 and 16 mm/min axial feed, C texture component {001}〈110〉 evolved in all layers, and the selective grain growth mechanism resulted in a sharp recrystallization texture.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"225 ","pages":"Article 115088"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895193","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}

{"title":"Structural origin for the insulator-metal transition in LaTiO3 thin films","authors":"Beibei Qiao ,&nbsp;Tingting Yao ,&nbsp;Xuexi Yan ,&nbsp;Neng He ,&nbsp;Qianqian Jin ,&nbsp;Zhiqing Yang ,&nbsp;Hengqiang Ye ,&nbsp;Chunlin Chen","doi":"10.1016/j.matchar.2025.115085","DOIUrl":"10.1016/j.matchar.2025.115085","url":null,"abstract":"<div><div>LaTiO₃ is a typical perovskite Mott-Hubbard insulator that exhibits abundant electrical properties. The extremely small band gap of LaTiO₃ facilitates the metal-insulator transition and makes the electrical properties easy to control. In this study, the electrical properties and microstructure of LaTiO₃ thin films fabricated on different substrates by pulse laser deposition have been investigated. Hall-effect measurements reveal that the LaTiO₃/LaAlO₃ thin film is an n-type semiconductor with low carrier mobility, carrier density and Hall coefficient, while the LaTiO₃/SrTiO₃ thin film exhibits a metallic conductivity with high carrier mobility, carrier density and Hall coefficient. TEM characterizations reveal that both films are epitaxial and the densities of domain boundaries are similar. However, the LaTiO₃/SrTiO₃ interface is coherent, suggesting that the LaTiO₃ film undergoes a strong compressive strain induced by the SrTiO₃ substrate. On the contrast, the LaTiO₃/LaAlO₃ interface is a semi-coherent interface and the strain in the LaTiO₃ film is released due to the formation of misfit dislocations. XPS and EELS analyses suggest that both films comprise Ti³⁺ and Ti⁴⁺ ions but the LaTiO₃/SrTiO₃ thin film has a higher concentration of Ti⁴⁺ ions. EDS measurements reveal that the LaTiO₃/SrTiO₃ thin film contains ~2 at.% Sr due to the Sr diffusion from the substrate. These results suggest that the high compressive strain and the elemental doping of Sr in the LaTiO₃/SrTiO₃ thin film should be the structural origin for the insulator-metal transition.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115085"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881349","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}

{"title":"Enhanced photoluminescence dynamics, fluorescence decay and distinctive electrical properties of Eu2O3 nanoparticles decorated liquid crystal nanocomposites","authors":"Nidhi Manhas ,&nbsp;Lalita S. Kumar ,&nbsp;Pankaj Kumar ,&nbsp;Vandna Sharma ,&nbsp;Rajeev S. Joshi ,&nbsp;Rangappa Keri ,&nbsp;A.K. Swetha ,&nbsp;Vinayak Adimule","doi":"10.1016/j.matchar.2025.115083","DOIUrl":"10.1016/j.matchar.2025.115083","url":null,"abstract":"<div><div>Herein, the reported work explored enhancement in photoluminescence, fluorescence decay, and electrical properties of rare-earth inorganic Europium oxide (Eu₂O₃) nanoparticles decorated 3b, 3c liquid crystal (LC) molecules. The textures of (<em>E</em>)-1-(4-pentoxy-3-fluorophenyl)-2-(4-butylphenyl) diazene (3b) @Eu₂O₃, (<em>E</em>)-1-(4-hexoxy-3-fluorophenyl)-2-(4-butylphenyl) diazene (3c) @Eu₂O₃ LC-nanocomposites (LC-NCs) showed birefringent mesophases with platelet/band-like and pebbles/marble-like structures, respectively. Steady-state photoluminescence revealed sharp/broad emission peaks at [551.8 nm, 553 nm (blue)]/422 nm (violet) for 3b@Eu₂O₃, 3c@Eu₂O₃ LC-NCs. Fluorescence decay lifetimes were between 0.231 ns–0.410 ns and 0.156 ns–0.528 ns, for 3b@Eu₂O₃ and 3c@Eu₂O₃ LC-NCs, respectively; and quantum yield was lower at the higher excitation wavelengths. Further, capacitance-voltage studies indicated symmetric permittivity of Eu₂O₃ on 3b, 3c LCs during heating cycle with applied voltage; while cooling mild reorientation at 6.3 V (positive) and 6.6 V (negative) was observed. Polarization vs. voltage studies unveiled no remnant polarization, and PFUND analysis revealed that polarization does not follow pulse rate and delay even at 10 V. Thus, the photoluminescent and electrical behavior of prepared LC-NCs pave the way for advancing photonic, and electro-optical devices.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115083"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881352","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}

{"title":"Phase transformation induced by severe gradient shear deformation in an Al0.1CoCrFeNi alloy","authors":"Wanyi Yang ,&nbsp;Hui Sheng ,&nbsp;Zhaowen Geng ,&nbsp;Yuhang Shi ,&nbsp;Pengda Niu ,&nbsp;Ruidi Li ,&nbsp;Xiaolong Ma ,&nbsp;Yanxia Liu ,&nbsp;Gang Zhou ,&nbsp;Kechao Zhou ,&nbsp;Miao Song","doi":"10.1016/j.matchar.2025.115074","DOIUrl":"10.1016/j.matchar.2025.115074","url":null,"abstract":"<div><div>High-entropy alloys (HEAs) are emerging as promising wear-resistant materials for engineering applications, owing to their exceptional mechanical properties and wear resistance. Nevertheless, the atomic friction and wear mechanisms of HEAs remains poorly understood, limiting the establishment of a comprehensive microstructure evolution framework that spans multiple length scales. Here, in-situ TEM was employed to investigate atomic scale friction and wear mechanisms of an Al_0.1CoCrFeNi alloy. The results reveal that the phase transformation from [011]_FCC to [001]_FCC, induced by the frictional gradient shear deformation, is correlated with significant strain relaxation at the intersections of stacking faults near the scratch surface. Additionally, numerous intermediate phases, resulting from lattice contraction and expansion due to atomic slip within the {111} planes, are observed in the friction subsurface. These findings enhance fundamental understanding of atomic-scale friction mechanisms in HEAs and provide valuable insights into the underlying damage mechanisms of wear-resistant materials subjected to friction-induced shear deformation.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115074"},"PeriodicalIF":4.8,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143881354","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}

{"title":"Effect of deposition sequence on microstructure and mechanical properties of 18Ni300 – Ni20 fabricated using laser-directed energy deposition","authors":"Junxin Zhou ,&nbsp;Min Fang ,&nbsp;Guangyu Wu ,&nbsp;Gang Xu ,&nbsp;Haifei Lu ,&nbsp;Kaiyu Luo ,&nbsp;Igor V. Alexandrov ,&nbsp;Jinzhong Lu","doi":"10.1016/j.matchar.2025.115068","DOIUrl":"10.1016/j.matchar.2025.115068","url":null,"abstract":"<div><div>In this work, laser-direct energy deposition was employed to fabricate 18Ni300<img>Ni20 laminated heterostructures. The microstructures of two different components (the 18Ni300/Ni20 component: depositing Ni20 on 18Ni300, and the Ni20/18Ni300 component: depositing Ni20 on 18Ni300) were analyzed using OM, SEM, and EBSD techniques. The distribution of microhardness and tensile characteristics was examined to assess the interfacial bonding strength. The microhardness of 18Ni300 at the Ni20/18Ni300 component reaches 430.49 HV, which is significantly higher than that of the 18Ni300/Ni20 component at 261.33 HV. This is attributed to the prolonged high temperatures resulting in the transformation of martensite to austenite, which is less hard than martensite. Ni20 exhibited a stable microhardness of 351.12 HV at the interfaces. The 18Ni300/Ni20 component demonstrated a superior ultimate tensile strength of 757 MPa compared to the Ni20/18Ni300 component, which exhibited a strength of 256 MPa. This is ascribed to a confluence of three factors: the combination of different crystal structures; interlocking structures at interfaces; and extensive diffusion of elements. The results of this study inform 3D printing, control of organization, and mechanical properties of martensitic Fe<img>Ni alloy components.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115068"},"PeriodicalIF":4.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887253","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}

{"title":"Effect of WC content on microstructure, mechanical properties, and tribo-corrosion behavior of laser-cladded Ni40A/WC composite coatings on H13 steel","authors":"Liangjie Xu ,&nbsp;Shengyuan Sun ,&nbsp;Jianan Xia ,&nbsp;Zihan Liu ,&nbsp;Weijie Deng ,&nbsp;Jiaxin Li ,&nbsp;Tao Wu ,&nbsp;Xinru Zhu ,&nbsp;Zhihao Lv ,&nbsp;Jicheng Gao ,&nbsp;Junke Jiao","doi":"10.1016/j.matchar.2025.115072","DOIUrl":"10.1016/j.matchar.2025.115072","url":null,"abstract":"<div><div>Ni40A/WC composite coatings were fabricated on H13 steel substrates via laser cladding technology, and the influence of WC content on the microstructure, microhardness, wear resistance, and corrosion resistance of the coatings was systematically investigated. The results demonstrate that an optimal WC content results in a Ni40A/WC composite coating with a smooth surface and dense microstructure. The addition of WC significantly enhances the nucleation rate, promotes grain refinement, and alters the preferential orientation of grain growth as well as the texture formation. Furthermore, the decomposition of WC leads to the formation of a W₂C hard phase. With increasing WC content, the microhardness and wear resistance of the coatings are markedly improved. Specifically, the microhardness of coatings with 0 wt%, 15 wt%, 30 wt%, and 45 wt% WC content is 1.7, 1.98, 2.17, and 2.48 times higher than that of the H13 substrate, respectively. Correspondingly, the wear rate is reduced by 39.14 %, 56.55 %, 73.88 %, and 82.59 % compared to the H13 substrate. In the absence of WC, the wear mechanism is dominated by adhesive wear accompanied by minor delamination wear. However, the introduction of WC transforms the wear mechanism to abrasive wear. In terms of corrosion resistance, the composite coating exhibits enhanced performance only when the WC content is below 30 %, as indicated by a positive shift in the self-corrosion potential and a decreased corrosion rate relative to the H13 substrate.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115072"},"PeriodicalIF":4.8,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874690","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}

{"title":"Temperature effect on adiabatic shear phenomenon and microstructure evolution of directional energy deposition 316 L stainless steel","authors":"Jining Li ,&nbsp;Dong Gao ,&nbsp;Yong Lu ,&nbsp;Qinghe Guan ,&nbsp;Kenan Deng","doi":"10.1016/j.matchar.2025.115079","DOIUrl":"10.1016/j.matchar.2025.115079","url":null,"abstract":"<div><div>Considering that the effect of temperature on the microstructural evolution and mechanical behavior of directed energy deposited (DED) 316 L stainless steel under high strain rates remains unclear, this study analyzes the macro/micro deformation behavior of DED-316 L under different temperatures and strain rates. It was observed that at 5000 s⁻¹ and 20 °C, adiabatic shear bands formed, whereas when the temperature increased to 400 °C, the adiabatic shear bands transformed into deformation bands. Moreover, the increase in temperature led to a 67.07 % reduction in geometrically necessary dislocation density. At a strain rate of 4000 s⁻¹, the effect of temperature on the twin percentage after material deformation was analyzed using Transmission Electron Microscopy. At 20 °C, the twin volume fraction was 35 %, while at 400 °C, the increased temperature raised the critical stress for twinning, and the twin percentage decreased to 9 %, a reduction of 74.29 %. A constitutive equation based on dislocation density evolution behavior was established to predict the stress-strain curve changes under high strain rates and high-temperature conditions. By comparing the predicted average geometrically necessary dislocation density with the experimentally obtained stress-strain curve, a Pearson correlation coefficient of 0.96 was obtained, confirming the accuracy of the model. This study provides important insights into the relationship between the macro/microstructural evolution and mechanical behavior of DED-316 L under dynamic loading conditions.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"224 ","pages":"Article 115079"},"PeriodicalIF":4.8,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891874","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}