为了改善7075-T6铝合金熔化焊接头的力学性能,提出了随焊余高碾压(welding with reinforcement rolling,WR)方法,采用自行设计的随焊碾压装置在焊接过程中对焊缝余高同步进行碾压,利用万能试验机和维氏硬度计对不同工艺参数下的不同接...为了改善7075-T6铝合金熔化焊接头的力学性能,提出了随焊余高碾压(welding with reinforcement rolling,WR)方法,采用自行设计的随焊碾压装置在焊接过程中对焊缝余高同步进行碾压,利用万能试验机和维氏硬度计对不同工艺参数下的不同接头进行力学性能测试,并通过配置能谱仪(energy dispersive spectrometer,EDS)和电子背散射衍射(electron back scatter diffraction,EBSD)探头的扫描电镜对电弧焊接试样和随焊碾压试样的焊缝区和热影响区分别进行组织观察.结果表明,随焊余高碾压工艺成功通过一次成形获得7075-T6铝合金高强度焊接接头,接头强度系数最高达到81.4%,相对电弧焊接头提升41.9%,焊缝强度的提高主要由于位错密度的增大和小角度晶界的增加,而晶粒尺寸及第二相分布对接头力学性能的影响比较小.创新点:(1)将随焊余高碾压工艺应用于7系铝合金.(2)随焊余高碾压工艺成功通过一次成形获得高强铝合金高强度焊接接头.(3)焊缝强度的提高主要由于位错密度的增大和小角度晶界的增加.展开更多
本研究旨在探讨肝复胶囊(Gan Fu capsule, GFC)对TGF-1诱导HSC-T6细胞增殖的影响及作用机制。试验采用制备空白血清和GFC含药血清,体外培养HSC-T6细胞24 h后,CCK8法筛选最佳给药血清浓度,采用不同浓度TGF-1诱导HSC-T6细胞,CCK8法筛选最...本研究旨在探讨肝复胶囊(Gan Fu capsule, GFC)对TGF-1诱导HSC-T6细胞增殖的影响及作用机制。试验采用制备空白血清和GFC含药血清,体外培养HSC-T6细胞24 h后,CCK8法筛选最佳给药血清浓度,采用不同浓度TGF-1诱导HSC-T6细胞,CCK8法筛选最佳造模浓度,将细胞分为空白组(CON)、模型组(MOD)、肝复胶囊低剂量组(GFC-L)、肝复胶囊中剂量组(GFC-M)、肝复胶囊高剂量组(GFC-H),采用细胞增殖检测(CCK8)法检测各组细胞增殖情况,酶联免疫吸附试验(ELISA)检测IL-6、IL-1 、TNF-含量,蛋白免疫印记试验(Western blot)检测各细胞中核苷酸结合寡聚化结构域样受体蛋白3(Nod-like receptor protein 3,NLRP3)、凋亡相关斑点样蛋白(Apoptosis associated speck-like protein containing a caspase activating recruitment domain, ASC)、半胱氨酸蛋白酶-1(Cysteinyl aspartate specific proteinase-1,Caspase-1)及-平滑肌动蛋白(Alpha-smooth muscle actin,-SMA)的表达。结果表明,与CON组相比,GFC能抑制HSC-T6细胞的增殖能力,减少HSC分泌IL-6、IL-1 、TNF-含量,降低HSC中NLRP3、ASC、Caspase-1及-SMA的表达量。GFC可能通过调节NLRP3/ASC/Caspase-1信号通路和减少-SMA蛋白表达,从而抑制HSC-T6增殖,起到抗肝纤维化的作用。展开更多
According to surface morphology,microhardness,X-ray diffraction,and static contact angle experiments,the changes in the surface integrity and corrosion resistance of 6061-T6 aluminum alloy after ultrasonic shot peenin...According to surface morphology,microhardness,X-ray diffraction,and static contact angle experiments,the changes in the surface integrity and corrosion resistance of 6061-T6 aluminum alloy after ultrasonic shot peening(USP)were investigated.Results show that the grain size of the material surface is reduced by 43%,the residual compressive stress has an increasing trend,the roughness and hardness are increased by approximately 211.1%and 35%,respectively.And the static contact angle is increased at first,followed by a slight decrease.Weighing,scanning electron microscope,and energy dispersive spectrometer were used to study the samples after a cyclic corrosion test.Results show that USP reduces the corrosion rate by 41.2%.A model of surface corrosion mechanism of USP is developed,and the mechanism of USP to improve the corrosion resistance of materials is discussed.The introduction of compressive residual stresses,grain refinement,increased grain boundaries,increased hardness,and increased static contact angle are the main factors related to the improvement of corrosion resistance in most materials,while increased roughness tends to weaken surface corrosion resistance.展开更多
文摘为了改善7075-T6铝合金熔化焊接头的力学性能,提出了随焊余高碾压(welding with reinforcement rolling,WR)方法,采用自行设计的随焊碾压装置在焊接过程中对焊缝余高同步进行碾压,利用万能试验机和维氏硬度计对不同工艺参数下的不同接头进行力学性能测试,并通过配置能谱仪(energy dispersive spectrometer,EDS)和电子背散射衍射(electron back scatter diffraction,EBSD)探头的扫描电镜对电弧焊接试样和随焊碾压试样的焊缝区和热影响区分别进行组织观察.结果表明,随焊余高碾压工艺成功通过一次成形获得7075-T6铝合金高强度焊接接头,接头强度系数最高达到81.4%,相对电弧焊接头提升41.9%,焊缝强度的提高主要由于位错密度的增大和小角度晶界的增加,而晶粒尺寸及第二相分布对接头力学性能的影响比较小.创新点:(1)将随焊余高碾压工艺应用于7系铝合金.(2)随焊余高碾压工艺成功通过一次成形获得高强铝合金高强度焊接接头.(3)焊缝强度的提高主要由于位错密度的增大和小角度晶界的增加.
基金Introduction of Talent Research Start-up Fund of Anhui University of Science and Technology(2022yjrc35)Colleges and Universities Excellent Young Talents Domestic Visit Research Project of Anhui Province(gxgnfx2022006)。
文摘According to surface morphology,microhardness,X-ray diffraction,and static contact angle experiments,the changes in the surface integrity and corrosion resistance of 6061-T6 aluminum alloy after ultrasonic shot peening(USP)were investigated.Results show that the grain size of the material surface is reduced by 43%,the residual compressive stress has an increasing trend,the roughness and hardness are increased by approximately 211.1%and 35%,respectively.And the static contact angle is increased at first,followed by a slight decrease.Weighing,scanning electron microscope,and energy dispersive spectrometer were used to study the samples after a cyclic corrosion test.Results show that USP reduces the corrosion rate by 41.2%.A model of surface corrosion mechanism of USP is developed,and the mechanism of USP to improve the corrosion resistance of materials is discussed.The introduction of compressive residual stresses,grain refinement,increased grain boundaries,increased hardness,and increased static contact angle are the main factors related to the improvement of corrosion resistance in most materials,while increased roughness tends to weaken surface corrosion resistance.
