【作者】 孙军； 韩礼红； 李梁；

【Author】 SUN Jun HAN Lihong LI Liang(State Key Laboratory for Mechanical Behavior of Materials,Xi’an Jiaotong University,Xi’an 710049)

【机构】 西安交通大学材料学院金属材料强度国家重点实验室；

【摘要】 利用扫描及透射电镜对爆炸焊接LY12/Al/LY12层合板内不同厚度纯铝层塑性变形及位错运动进行了研究。结果表明:中间纯铝层的塑性变形行为明显不同于块体纯金属,其厚度尺寸对材料的韧脆转变具有显著影响。加载过程中中间纯铝层裂端发射的位错在附近晶界形成塞积,塞积密度随其厚度下降明显增加,晶界的强化效应显著增强。更多还原

【Abstract】 In situ tensile test,by scanning and transparent electronic microscope,were conducted to observe the plastic deformation and dislocations motion in pure Al sheet with different thickness,h,sandwiched by 2024 alloy with higher strength through explosive cladding. The results show that the plastic deformation is obviously different from that of bulk metal and the thickness plays a key role on the ductile to brittle transition in Al interlayer. In the inter Al layer dislocations emitted from crack tip glide around and pile up against grain boundaries nearby. As h decreasing the pile-up density remarkably increases,much higher than that in bulk Al,and the grains strengthening effect is far beyond that in bulk metal.更多还原