Journal of Materials Research and Technology-Jmr&t最新文献

{"title":"Phase reversion mediated the dual heterogeneity of grain size and dislocation density in an equiatomic CrCoNi medium-entropy alloy","authors":"Kun Jiang ,&nbsp;Jianguo Li ,&nbsp;Xi Chen ,&nbsp;Bin Gan ,&nbsp;Qingbo Dou ,&nbsp;Tao Suo","doi":"10.1016/j.jmrt.2024.09.080","DOIUrl":"10.1016/j.jmrt.2024.09.080","url":null,"abstract":"<div><p>An ultra-high strain rate (10⁴ s⁻¹) dynamic plastic deformation treatment at liquid nitrogen temperature (LNT-DPD) followed by annealing is carried out to obtain dual heterogeneity of grain size and dislocation density in an equiatomic CrCoNi medium entropy alloy (MEA). Such extreme loading conditions resulted in extensive phase transformation in this MEA. Subsequent annealing at 650 °C for 1 h further induced reverse phase transformation and partial recrystallization, forming a complex heterogeneous microstructure characterized by nested trimodal grain sizes and partitioned dislocation density. A superior yield strength of ∼800 MPa and a good ductility of ∼40% were simultaneously achieved in this heterogeneous alloy. In order to reveal the effects of grain size and dislocation density distributions on the mechanical property improvements, the underlying deformation mechanisms were systematically discussed. High density of geometrically necessary dislocations (GNDs) would be induced in complex heterogeneous structures during tensile deformation due to strain gradients or partitioning between different regions, which would lead to additional strengthening and work hardening. These results provide a novel approach to overcome the strength-ductility trade-off dilemma for FCC-structured MEAs.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 471-479"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424020842/pdfft?md5=c1b777811653e66a6c84b73f4b336854&pid=1-s2.0-S2238785424020842-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238272","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}

{"title":"Reaction mechanisms and mechanical properties of SiCf/SiC composite and GH536 superalloy joints using CoFeNiCrMn high-entropy alloy filler","authors":"Buqiu Shao ,&nbsp;Shuai Zhao ,&nbsp;Peng Wang ,&nbsp;Xin Nai ,&nbsp;Haiyan Chen ,&nbsp;Yongsheng Liu ,&nbsp;Pengcheng Wang ,&nbsp;Xiaoguo Song ,&nbsp;Wenya Li","doi":"10.1016/j.jmrt.2024.09.095","DOIUrl":"10.1016/j.jmrt.2024.09.095","url":null,"abstract":"<div><p>To meet the service conditions and strength requirements of turbine stator blades and the inner and outer rings of aero engine casings, CoFeNiCrMn high-entropy alloy filler was used to braze SiC_f/SiC/GH536 joints. This study investigated the effects of holding time on the joints' microstructure and mechanical properties. Key phases identified in the welded joints include MoNiSi, FCC, and Cr₂₃C₆ near the composites, with brittle Ni₃Si and Fe₂Si intermetallic compounds forming due to filler diffusion. Optimal brazing parameters were found to be 1220 °C for 30 min with a shear strength of 64.28 MPa. The study also highlighted that increased holding time at the same temperature enhances diffusion at the joint, increasing brittle intermetallic compounds, initially improving shear strength, which then declines. Microstructural and fracture morphology analyses revealed that insufficient insulation time leads to poor welding and stress concentration at pores, causing cracks. Excessive insulation time results in joint fractures due to the brittleness of Ni₃Si and Fe₂Si intermetallic. Thus, joint shear strength correlates with welding quality and intermetallic compound distribution.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 491-502"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S223878542402101X/pdfft?md5=6bb16ad2e9a89c2ed4e47ecee64eb04f&pid=1-s2.0-S223878542402101X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238274","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}

{"title":"Microstructure evolution and properties of semi-solid Al80Mg5Li5Zn5Cu5 light weight high entropy alloy prepared by SIMA","authors":"Yong Hu ,&nbsp;Yuanyuan Liu","doi":"10.1016/j.jmrt.2024.09.085","DOIUrl":"10.1016/j.jmrt.2024.09.085","url":null,"abstract":"<div><p>The semi-solid Al₈₀Mg₅Li₅Zn₅Cu₅ light weight high entropy alloys were prepared by strain induced melting activation method (SIMA), and the microstructure evolution, mechanical properties and corrosion resistance of semi-solid Al₈₀Mg₅Li₅Zn₅Cu₅ light weight high entropy alloys were investigated. The results indicate that the ideal globular or near-globular microstructures with an average grain size of 29.1 μm and a shape factor of 0.86 can be obtained when the Al₈₀Mg₅Li₅Zn₅Cu₅ light weight high entropy alloys with 20% deformation held at 500 °C for 15 min. The coarsening coefficient is 35.8 μm³/s when the temperature is 500 °C, which is lower than the traditional single major element alloys due to the sluggish diffusion effect of high entropy alloys. The compression strength of semi-solid Al₈₀Mg₅Li₅Zn₅Cu₅ light weight high entropy alloys is 558.4 MPa, which is 11% higher than that of as-cast state. The corrosion resistance of semi-solid Al₈₀Mg₅Li₅Zn₅Cu₅ light weight high entropy alloys is also significantly improved.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 965-974"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424020908/pdfft?md5=730f62cb2a4164547b931615915d72f4&pid=1-s2.0-S2238785424020908-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270866","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}

{"title":"Influence of strength difference between soft and hard zones on hetero-deformation induced strengthening effect: Taking heterostructured β Ti alloy as an example","authors":"Z.Q. Li ,&nbsp;B. Sang ,&nbsp;Q. Wang ,&nbsp;Y.K. Wu ,&nbsp;J.Q. Ren ,&nbsp;C. Xin ,&nbsp;T.T. Ai","doi":"10.1016/j.jmrt.2024.09.022","DOIUrl":"10.1016/j.jmrt.2024.09.022","url":null,"abstract":"<div><div>The large strength difference between soft and hard zones in heterostructured materials is a double-edged sword: on the one hand, the effective back (<span><math><mrow><msub><mi>τ</mi><mi>b</mi></msub></mrow></math></span>) and forward stress (<span><math><mrow><msub><mi>τ</mi><mi>f</mi></msub></mrow></math></span>) are generated to produce hetero-deformation induced (HDI) strengthening and strain hardening effect. On the other hand, the micro-cracks tend to initiate and propagate along the interface to cause premature failure. Here we prepared three different heterostructured Ti-4.8Al-5.6Mo–3V-1.5Cr-1.6Fe alloys to reveal the influence of magnitude of strength difference between soft primary α phase (α_p) and hard β matrix on its tensile strength and ductility. It demonstrates that only when the sum of applied stress (<span><math><mrow><msub><mi>τ</mi><mi>a</mi></msub></mrow></math></span>) and <span><math><mrow><msub><mi>τ</mi><mi>f</mi></msub></mrow></math></span> is greater than the yield strength of hard β matrix (<span><math><mrow><msubsup><mi>σ</mi><mi>y</mi><mrow><mi>h</mi><mi>a</mi><mi>r</mi><mi>d</mi></mrow></msubsup></mrow></math></span>), i.e., <span><math><mrow><msub><mi>τ</mi><mi>a</mi></msub><mo>+</mo><msub><mi>τ</mi><mi>f</mi></msub><mo>&gt;</mo><msubsup><mi>σ</mi><mi>y</mi><mrow><mi>h</mi><mi>a</mi><mi>r</mi><mi>d</mi></mrow></msubsup></mrow></math></span>, the alloy can obtain both high strength and ductility. Contrary, when <span><math><mrow><msub><mi>τ</mi><mi>a</mi></msub><mo>+</mo><msub><mi>τ</mi><mi>f</mi></msub><mo>&lt;</mo><msubsup><mi>σ</mi><mi>y</mi><mrow><mi>h</mi><mi>a</mi><mi>r</mi><mi>d</mi></mrow></msubsup></mrow></math></span>, the alloy exhibits a highest strength but a lowest ductility. These findings are expected to help with designing heterostructured materials for superior mechanical properties.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 1730-1739"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142319477","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}

{"title":"Hydrogen-peroxide intercalated expanded graphite facilitates large enhancement in thermal conductivity of polyetherimide/graphite nanocomposites","authors":"Fatema Tarannum ,&nbsp;Swapneel Danayat ,&nbsp;Avinash Nayal ,&nbsp;Zarin Tasnim Mona ,&nbsp;Roshan Sameer Annam ,&nbsp;Keisha B. Walters ,&nbsp;Jivtesh Garg","doi":"10.1016/j.jmrt.2024.09.043","DOIUrl":"10.1016/j.jmrt.2024.09.043","url":null,"abstract":"<div><div>In this work, we prepared expanded graphite (EG) filler using hydrogen peroxide (H₂O₂) as an oxidizing agent to study its impact on the thermal conductivity (<em>k</em>) of polyetherimide (PEI) composite, compared to EG prepared using sodium chlorate (NaClO₃). Sulfuric acid was used as the primary intercalating agent for both synthesis routes. The use of H₂O₂ prepared EG (EG-H₂O₂) led to a remarkable ∼4030% enhancement (9.5 Wm⁻¹K⁻¹) in <em>k</em> of the PEI/EG composite, while the use of NaClO₃ prepared EG (EG-NaClO₃) led to a much smaller enhancement of ∼2190% (5.3 Wm⁻¹K⁻¹), at 10 wt% EG composition compared to <em>k</em>_PEI (∼0.23 Wm⁻¹K⁻¹). Such findings exceed the current state-of-art in EG-based polymer composites. Detailed characterization was performed to understand the properties of EG-H₂O₂ and EG-NaClO₃. Raman analysis revealed that H₂O₂ resulted in relatively defect-free EG (I_D/I_G ratio ∼0.04), thus preserving the <em>k</em> of graphite (∼2000 Wm⁻¹K⁻¹). Use of NaClO₃, however, led to a large defect density (I_D/I_G ratio ∼0.25), yielding graphite with significantly diminished <em>k</em>. Furthermore, through-plane thermal diffusivity of EG-H₂O₂ paper was measured to be 9.5 mm²s^-1 while that of NaClO₃ case was measured to be 6.7 mm²s^-1, thus directly confirming the beneficial impact of H₂O₂ in preserving the high <em>k</em> of graphene. X-ray photoelectron spectroscopy (XPS) revealed that the higher number of defects in EG-NaClO₃ are due to the higher degree of oxidation induced by NaClO₃. The results demonstrate the potential of EG-H₂O₂ as an efficient filler for achieving high thermal conductivity polymer composites.</div></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 1420-1435"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424020490/pdfft?md5=f1a713aa0e1dcaa8ce2eb8f9068a3335&pid=1-s2.0-S2238785424020490-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142312288","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}

{"title":"A study on anisotropic hardening of 7075 aluminum alloy based on non-associated flow rules","authors":"Xiaodong Wu ,&nbsp;Zhen Zhang ,&nbsp;Wenkang Zhang","doi":"10.1016/j.jmrt.2024.09.084","DOIUrl":"10.1016/j.jmrt.2024.09.084","url":null,"abstract":"<div><p>The accurate description of anisotropic plastic deformation is key to accurately predicting the stamping forming of metal sheets. The anisotropic yield criterion, when based on the assumption of isotropic hardening, often leads to significant inaccuracies. To address this issue, this paper observes the anisotropic hardening phenomenon through non-associated flow rules and evaluates the anisotropy of 7075-O aluminum alloy. Through a series of tensile tests, we determined the mechanical properties of 7075-O aluminum alloy in three distinct orientations. To describe the metal hardening behavior, we employed the Swift-Voce hardening criterion. From the hardening curves in three different directions, it was found that AA7075-O exhibits plastic anisotropy. Based on the VUMAT subroutine, finite element simulation of AA7075-O tensile tests was conducted through Abaqus. Compared with the Hill48 model, it was found that the simulated values of the S–Y2009 anisotropic hardening model have a higher degree of agreement with the experimental curves. The S–Y2009 anisotropic hardening model was adopted to predict the earing behavior of AA7075-O during circular cup deep drawing. The root mean square error between the predicted values of the S–Y2009 model and the experimental values was only 0.1795, which is far smaller than that of the Hill48 yield model. Therefore, the SY2009 model has important guiding significance for the stamping forming of metal sheets.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 612-619"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424020891/pdfft?md5=475a890f75933e6b950c1cc989322a22&pid=1-s2.0-S2238785424020891-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142238351","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}

{"title":"Improving dynamic mechanical properties and inhibiting adiabatic shear bands of the molybdenum single crystal by adding Nb element","authors":"Zhenchuan Li ,&nbsp;Benqi Jiao ,&nbsp;Weiwei Zhang ,&nbsp;Wen Zhang ,&nbsp;Jianfeng Li","doi":"10.1016/j.jmrt.2024.09.082","DOIUrl":"10.1016/j.jmrt.2024.09.082","url":null,"abstract":"<div><p>The adiabatic shear band is a common dynamic failure mechanism in metal materials at high strain rates. In this work, a new approach was proposed to improve mechanical properties and inhibit the formation and propagation of the adiabatic shear band in the pure Mo single crystal. The microstructure evolution of the pure Mo and Mo-Nb single crystals subjected to the dynamic load was investigated by EBSD and TEM. At a strain rate of 2500 s⁻¹, the developed adiabatic shear band was totally distributed in the pure Mo single crystal, and the slip is the main deformation mechanism. A thinner adiabatic shear band was distributed in the Mo-3Nb single crystal accompanied by a few bands of deformation twins and then disappeared in the Mo-6Nb single crystal, replaced by the {112}&lt;111&gt; deformation twinning. At high strain rates, the dynamic deformation mechanism of the Mo single crystal is sensitive to the Nb element, which attributes to the reduction of the generalized stacking fault energy.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 1176-1187"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S223878542402088X/pdfft?md5=62bbd2b25ab4f3b5598d2038140d8510&pid=1-s2.0-S223878542402088X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270364","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}

{"title":"Substructure boundary's enhancing strain hardening ability in additively manufactured 0.75 at%C doping NiCoCr medium entropy alloy","authors":"So-Yeon Park ,&nbsp;Ji-Eun Ahn ,&nbsp;Young-Kyun Kim ,&nbsp;Kreethi Ravi ,&nbsp;Kee-Ahn Lee","doi":"10.1016/j.jmrt.2024.09.086","DOIUrl":"10.1016/j.jmrt.2024.09.086","url":null,"abstract":"<div><p>In this study, the effect of post heat treatment on microstructural evolution and tensile properties of 0.75% of carbon doped NiCoCr MEA alloy manufactured by laser powder bed fusion (LPBF) was investigated. The post heat treatment of LPBF-built 0.75C MEA alloy was selected and carried out at 700 °C for 1hr, respectively. The microstructural observation in heat-treated 0.75C MEA HT sample shows a lower stacking fault energy (SFE) with wider stacking fault width (SFW) compared to as-built condition. In-situ nano-sized precipitates are formed along the sub-boundaries of the as₋built 0.75C MEA and 0.75C MEA HT samples which are estimated as 1.25 % and 2.45 %, respectively. After post heat treatment process, the size and ratio of nano-sized precipitates enhanced and identified as Cr-rich M₂₃C₆ carbide. Subsequently, the yield and tensile strengths increase from 823.2 MPa to 872.7 MPa and 1.05 GPa–1.15 GPa for 0.75C MEA and 0.75C MEA HT conditions, respectively which is attributed to the prevailing solid solution strengthening and precipitation strengthening. The deformation twins in as−built specimen are transformed to twin bundle once the local strain increases from 5% to 20%. The 0.75C MEA HT deformed specimen exhibits high dislocation accumulation with retained stable substructure in local strain 20% area due to the pinning effect of nano-sized precipitates which stabilizes and strengthens the substructure boundary i.e., Dynamic Hall-Petch mechanism. These results provide a new perception for achieving better strength performance by post heat treatment process for NiCoCr-based medium entropy alloys (MEA) alloy.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 1087-1096"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S223878542402091X/pdfft?md5=b064f98d5d8d7fbbb7867bde1a7b9837&pid=1-s2.0-S223878542402091X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270367","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}

{"title":"Study on creep performance of shotcrete lining for tunnels","authors":"Yali Jia ,&nbsp;Lixi Zhao ,&nbsp;Lei Wang ,&nbsp;Qingyu Gao ,&nbsp;Baice Qiao ,&nbsp;Qingxin Zhao","doi":"10.1016/j.jmrt.2024.09.093","DOIUrl":"10.1016/j.jmrt.2024.09.093","url":null,"abstract":"<div><p>Creep, as a long-term deformation characteristic of shotcrete, significantly influences the load-bearing performance and durability of tunnel support structures. This study conducted creep tests on shotcrete under varying stress levels. The results reveal that shotcrete exhibits linear creep response within the stress range of 30%–40%, while the critical stress range for nonlinear creep response occurs between 40% and 50%. Employing SEM-EDS and XRD analysis methods, the impact of accelerator on the microstructure evolution and creep mechanism of shotcrete is explored. The accelerator accelerates the hydration of C₃S, promoting the generation of AFt and C–S–H gel, leading to rapid solidification of the matrix and enhanced early strength. With the consumption of SO₄²⁻ ions, AFt gradually transforms into AFm, resulting in increased matrix porosity. This phenomenon contributes to the reduced later-stage strength and substantial creep deformation of shotcrete. Based on experimental outcomes, this study evaluates the applicability of existing creep calculation models to shotcrete.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 1130-1139"},"PeriodicalIF":6.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424020969/pdfft?md5=ff2f0d74f708ba28a690b72a1d1b9831&pid=1-s2.0-S2238785424020969-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270368","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}

{"title":"Multi-angle analysis of Mo on martensite–austenite component and toughness in SCGHAZ of X80 pipeline automatic ring welding","authors":"Yuan Li ,&nbsp;Qingshan Feng ,&nbsp;Haidong Jia ,&nbsp;Shaohua Cui ,&nbsp;Lianshuang Dai ,&nbsp;Huibin Wu ,&nbsp;Qingyou Liu ,&nbsp;Hesong Zhang ,&nbsp;Shujun Jia","doi":"10.1016/j.jmrt.2024.09.062","DOIUrl":"10.1016/j.jmrt.2024.09.062","url":null,"abstract":"<div><p>In order to solve the embrittlement problem of welded joint of pipeline steel, this paper proposes to study the influence of Mo on M-A component of the subcritically reheated coarse-grained HAZ (SCGHAZ), and Mo on bainite transformation. Through the welding thermal simulation experiment, two kinds of X80 pipeline steel with different Mo content were set different secondary thermal cycle peak temperatures to simulate the heat affected zone (HAZ). Samples in the SCGHAZ were selected to observe the microstructure, M-A component, microalloy-element distribution and fracture crack trend, and comprehensively analyze the reasons for the deterioration of impact toughness caused by the changes of Mo content. The results show that the increase of Mo content leads to the formation of twinning martensite, which is one of the reasons for the deterioration of toughness. Mo is enriched at the interface of ferrite and M-A component, reducing the binding energy at the interface, resulting in the desorption of M-A component from the matrix, the formation of pores and becoming the nucleation site of cracks, resulting in the generation of micro-cracks and the decrease of toughness.</p></div>","PeriodicalId":54332,"journal":{"name":"Journal of Materials Research and Technology-Jmr&t","volume":"33 ","pages":"Pages 115-129"},"PeriodicalIF":6.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2238785424020672/pdfft?md5=4e8090ec683cdebffc3c774cdf4b650c&pid=1-s2.0-S2238785424020672-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173112","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}