Single-pass and double-pass high-temperature deformation experiments were conducted on 40Cr10Si2Mo steel using a Gleeble-3500 thermal simulator.The static recrystallization(SRX)behavior and recrystallization mechanism...Single-pass and double-pass high-temperature deformation experiments were conducted on 40Cr10Si2Mo steel using a Gleeble-3500 thermal simulator.The static recrystallization(SRX)behavior and recrystallization mechanisms of 40Cr10Si2Mo steel were investigated under deformation temperatures of 900-1100℃,deformation strains of 10%,20%,and 30%,and inter-pass times of 1-120 s.A static recrystallization fraction model was developed.The results showed that the SRX volume fraction increased with higher deformation temperature,larger deformation amount,and longer inter-pass time,with the deformation temperature having the most significant effect on SRX.During the deformation process,different process parameters led to different internal deformation mechanisms of the material.Static recovery and continuous static recrystallization(CSRX)dominated deformation at lower temperatures through progressive lattice rotation.In comparison,at higher temperatures,the deformation mechanism was dominated by CSRX and discontinuous static recrystallization(DSRX).The nucleation mechanisms of the SRX process were grain boundary bulging nucleation and subgrain merging nucleation,with grain boundary bulging present under all conditions.Subgrain merging nucleation could provide an additional nucleation mode at lower deformation temperatures or lower deformation amounts.Based on the traditional Avarmi equation,a modified model coefficient was used to establish the SRX kinetic model for 40Cr10Si2Mo steel.The linear correlation coefficient R^(2) between the predicted and experimental static recrystallization volume fraction was 0.96702,indicating high prediction accuracy.展开更多
The Cu0.9Cr0.1Zr alloy was deformed through continuous equal channel angular pressing(C-ECAP)through Route A,followed by liquid nitrogen cryogenic rolling(CR)and aging treated at 450℃.The microstructure,mechanical pr...The Cu0.9Cr0.1Zr alloy was deformed through continuous equal channel angular pressing(C-ECAP)through Route A,followed by liquid nitrogen cryogenic rolling(CR)and aging treated at 450℃.The microstructure,mechanical properties,and conductivity of the alloy were detected by electron back-scattered diffractometer,energy dispersive spectroscope,X-ray diffractometer,scanning electron microscope,and transmission electron microscope.The evolution mechanism of the texture during the deformation process and its influence on mechanical properties were analyzed.The results show that directional shear bands form in the CuCrZr alloy during the C-ECAP process,and the preferred orientation of the microstructure is consistent with the rolling direction.After deformation,the number of precipitated phases(mainly Cr)increases with the prolongation of aging time,accompanied by the appearance of micro-nanostructured fibrous structure in the alloy.After C-ECAP for three passes,75%CR deformation,and aging at 450℃ for 2 h,the tensile strength,microhardness,and conductivity reach 538 MPa,168 HV,and 80%IACS,respectively.CR,aging heat treatment,and formation of recrystallization texture are all conducive to the improvement of conductivity.展开更多
为探究汽爆豌豆蛋白肽Cr(Ⅲ)螯合物(steam-exploded pea protein peptides-chromium(Ⅲ)chelate,SEPPs-Cr(Ⅲ))的制备工艺及生物活性,以汽爆豌豆蛋白肽(steam-exploded pea protein peptides,SEPPs)作为原料与Cr(Ⅲ)进行螯合,以Cr(Ⅲ)...为探究汽爆豌豆蛋白肽Cr(Ⅲ)螯合物(steam-exploded pea protein peptides-chromium(Ⅲ)chelate,SEPPs-Cr(Ⅲ))的制备工艺及生物活性,以汽爆豌豆蛋白肽(steam-exploded pea protein peptides,SEPPs)作为原料与Cr(Ⅲ)进行螯合,以Cr(Ⅲ)螯合率为指标,通过单因素试验和响应面试验确定SEPPs-Cr(Ⅲ)的最佳制备条件,通过紫外-可见光谱、荧光光谱、傅里叶变换红外光谱、圆二色光谱、Zeta电位和粒径、扫描电子显微镜对螯合前后样品进行结构表征,并对其体外抗氧化活性和降糖活性进行评价。结果表明,SEPPs-Cr(Ⅲ)的最佳制备条件为肽溶液与Cr(Ⅲ)溶液体积比1∶3.7、pH 4.6、温度37.5℃、时间70 min,在此条件下螯合率达到(31.67±0.75)%。与SEPPs相比,SEPPs-Cr(Ⅲ)粒径增大,表面负电荷数量明显降低,β-折叠含量增加,无规卷曲含量减少,呈现出粗糙、折叠且致密的颗粒状聚集体外貌形态。此外,Cr(Ⅲ)主要与SEPPs肽链中的氨基、羰基和羧基结合,形成具有稳定结构的螯合物。体外生物活性结果表明,SEPPs-Cr(Ⅲ)对1,1-二苯基-2-三硝基苯肼自由基和羟自由基的半抑制浓度分别为5.14 mg/mL和4.6 mg/mL,显著低于SEPPs的11.6 mg/mL和8.79 mg/mL,对α-淀粉酶和α-葡萄糖苷酶半抑制浓度分别为0.39 mg/mL和0.59 mg/mL,显著低于SEPPs的3.14 mg/mL和9.18 mg/mL。此外,SEPPs-Cr(Ⅲ)的还原能力显著优于SEPPs。本研究结果可为开发有机补铬剂提供一定的理论依据。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.52174371)the National Key Research and Development Program of China(Grant No.2021YFB3501003)the Shaanxi Provincial Science and Technology Department Enterprise Joint Fund(Grant No.2021JLM-33).
文摘Single-pass and double-pass high-temperature deformation experiments were conducted on 40Cr10Si2Mo steel using a Gleeble-3500 thermal simulator.The static recrystallization(SRX)behavior and recrystallization mechanisms of 40Cr10Si2Mo steel were investigated under deformation temperatures of 900-1100℃,deformation strains of 10%,20%,and 30%,and inter-pass times of 1-120 s.A static recrystallization fraction model was developed.The results showed that the SRX volume fraction increased with higher deformation temperature,larger deformation amount,and longer inter-pass time,with the deformation temperature having the most significant effect on SRX.During the deformation process,different process parameters led to different internal deformation mechanisms of the material.Static recovery and continuous static recrystallization(CSRX)dominated deformation at lower temperatures through progressive lattice rotation.In comparison,at higher temperatures,the deformation mechanism was dominated by CSRX and discontinuous static recrystallization(DSRX).The nucleation mechanisms of the SRX process were grain boundary bulging nucleation and subgrain merging nucleation,with grain boundary bulging present under all conditions.Subgrain merging nucleation could provide an additional nucleation mode at lower deformation temperatures or lower deformation amounts.Based on the traditional Avarmi equation,a modified model coefficient was used to establish the SRX kinetic model for 40Cr10Si2Mo steel.The linear correlation coefficient R^(2) between the predicted and experimental static recrystallization volume fraction was 0.96702,indicating high prediction accuracy.
基金Gansu Provincial Department of Education Industrial Support Program Project(2025CYZC-069)Central Government-Guided Local Science and Technology Development Fund Project(25ZYJE002)National Natural Science Foundation of China(51861022,51261016)。
文摘The Cu0.9Cr0.1Zr alloy was deformed through continuous equal channel angular pressing(C-ECAP)through Route A,followed by liquid nitrogen cryogenic rolling(CR)and aging treated at 450℃.The microstructure,mechanical properties,and conductivity of the alloy were detected by electron back-scattered diffractometer,energy dispersive spectroscope,X-ray diffractometer,scanning electron microscope,and transmission electron microscope.The evolution mechanism of the texture during the deformation process and its influence on mechanical properties were analyzed.The results show that directional shear bands form in the CuCrZr alloy during the C-ECAP process,and the preferred orientation of the microstructure is consistent with the rolling direction.After deformation,the number of precipitated phases(mainly Cr)increases with the prolongation of aging time,accompanied by the appearance of micro-nanostructured fibrous structure in the alloy.After C-ECAP for three passes,75%CR deformation,and aging at 450℃ for 2 h,the tensile strength,microhardness,and conductivity reach 538 MPa,168 HV,and 80%IACS,respectively.CR,aging heat treatment,and formation of recrystallization texture are all conducive to the improvement of conductivity.
文摘为探究汽爆豌豆蛋白肽Cr(Ⅲ)螯合物(steam-exploded pea protein peptides-chromium(Ⅲ)chelate,SEPPs-Cr(Ⅲ))的制备工艺及生物活性,以汽爆豌豆蛋白肽(steam-exploded pea protein peptides,SEPPs)作为原料与Cr(Ⅲ)进行螯合,以Cr(Ⅲ)螯合率为指标,通过单因素试验和响应面试验确定SEPPs-Cr(Ⅲ)的最佳制备条件,通过紫外-可见光谱、荧光光谱、傅里叶变换红外光谱、圆二色光谱、Zeta电位和粒径、扫描电子显微镜对螯合前后样品进行结构表征,并对其体外抗氧化活性和降糖活性进行评价。结果表明,SEPPs-Cr(Ⅲ)的最佳制备条件为肽溶液与Cr(Ⅲ)溶液体积比1∶3.7、pH 4.6、温度37.5℃、时间70 min,在此条件下螯合率达到(31.67±0.75)%。与SEPPs相比,SEPPs-Cr(Ⅲ)粒径增大,表面负电荷数量明显降低,β-折叠含量增加,无规卷曲含量减少,呈现出粗糙、折叠且致密的颗粒状聚集体外貌形态。此外,Cr(Ⅲ)主要与SEPPs肽链中的氨基、羰基和羧基结合,形成具有稳定结构的螯合物。体外生物活性结果表明,SEPPs-Cr(Ⅲ)对1,1-二苯基-2-三硝基苯肼自由基和羟自由基的半抑制浓度分别为5.14 mg/mL和4.6 mg/mL,显著低于SEPPs的11.6 mg/mL和8.79 mg/mL,对α-淀粉酶和α-葡萄糖苷酶半抑制浓度分别为0.39 mg/mL和0.59 mg/mL,显著低于SEPPs的3.14 mg/mL和9.18 mg/mL。此外,SEPPs-Cr(Ⅲ)的还原能力显著优于SEPPs。本研究结果可为开发有机补铬剂提供一定的理论依据。
