通过金相试验、SEM试验、拉伸试验、冲击试验,分析不同焊接热输入下X90管线钢焊接接头的组织和力学性能。结果显示,当焊接热输入为15 k J/cm时,组织性能变化较小;焊接热输入增大至21 k J/cm时,接头焊缝区的显微组织晶粒变粗大,铁素体含...通过金相试验、SEM试验、拉伸试验、冲击试验,分析不同焊接热输入下X90管线钢焊接接头的组织和力学性能。结果显示,当焊接热输入为15 k J/cm时,组织性能变化较小;焊接热输入增大至21 k J/cm时,接头焊缝区的显微组织晶粒变粗大,铁素体含量增加,板条贝氏体含量减少,对强韧性影响不大;当热输入增大至30 k J/cm时,接头HAZ冲击吸收能量KV2急剧减小51 J。在焊接热输入为21 k J/cm时,由于板条贝氏体、铁素体、M/A和分布于基体上的粒状贝氏体共同作用,使X90管线钢焊接接头具有优良的组织和力学性能。展开更多
Three types of laminates were designed by alternately stacking AZ91 extruded sheets in different states for extrusion to improve the mechanical properties.The tensile tests revealed that the combination of solid-solut...Three types of laminates were designed by alternately stacking AZ91 extruded sheets in different states for extrusion to improve the mechanical properties.The tensile tests revealed that the combination of solid-solution-treated sheets with the aging-treated sheets achieved high tensile strength and ductility,i.e.,ultimate tensile strength of~386 MPa and elongation of~19.8%,respectively.Electron backscatter diffraction(EBSD)and TEM results indicated that the aging-treated layers with more nano-sized precipitates and small grain size provided high strength and reasonable ductility,while the solid-solution-treated layers with low dislocation density facilitated strain hardening.Also,the strong interface bonding between the successive layers played an important role in the enhanced ductility.展开更多
文摘通过金相试验、SEM试验、拉伸试验、冲击试验,分析不同焊接热输入下X90管线钢焊接接头的组织和力学性能。结果显示,当焊接热输入为15 k J/cm时,组织性能变化较小;焊接热输入增大至21 k J/cm时,接头焊缝区的显微组织晶粒变粗大,铁素体含量增加,板条贝氏体含量减少,对强韧性影响不大;当热输入增大至30 k J/cm时,接头HAZ冲击吸收能量KV2急剧减小51 J。在焊接热输入为21 k J/cm时,由于板条贝氏体、铁素体、M/A和分布于基体上的粒状贝氏体共同作用,使X90管线钢焊接接头具有优良的组织和力学性能。
基金The authors are grateful for the financial supports from the National Natural Science Foundation of China(Nos.52071035,U1764253).
文摘Three types of laminates were designed by alternately stacking AZ91 extruded sheets in different states for extrusion to improve the mechanical properties.The tensile tests revealed that the combination of solid-solution-treated sheets with the aging-treated sheets achieved high tensile strength and ductility,i.e.,ultimate tensile strength of~386 MPa and elongation of~19.8%,respectively.Electron backscatter diffraction(EBSD)and TEM results indicated that the aging-treated layers with more nano-sized precipitates and small grain size provided high strength and reasonable ductility,while the solid-solution-treated layers with low dislocation density facilitated strain hardening.Also,the strong interface bonding between the successive layers played an important role in the enhanced ductility.
