喷射沉积Al-2.15Li-1.28Mg-1.26Cu-0.10Zr合金的拉伸断裂行为

来源期刊：中国有色金属学报1997年第1期

论文作者：崔成松 范洪波 来忠红 蒋祖龄 李庆春 米国发

文章页码：138 - 142

关键词：喷射沉积 快速凝固 Al-Li合金 显微组织 拉伸性能

Key words：spray deposition rapid solidification Al-Li alloy microstructure tensile property

摘    要：采用新型的喷射沉积工艺制备了Al-2.15Li-1.28 Mg-1.26Cu-0.10Zr合金,对其不同时效状态的拉伸性能及断裂行为进行了研究。实验结果表明，喷射沉积Al-Li合金经190 ℃、20 h 时效后达到峰时效状 态，此时材料的综合性能最优(σb=528 MPa，σ0.2=420 MPa，延伸率为12%)。固溶淬火态实验合金拉伸断口为完全穿晶韧窝型。时效态合金的断裂方式为穿晶和沿晶混合型。随时效时间的延长，沿晶断裂的比例增加。实验合金沿晶断裂的原因是位错的共面滑移、晶界无析出区和晶界平衡相的析出。

Abstract: Al-2.15Li-1.28Mg-1.26Cu-0.10Zr alloy was prepared by spray deposition processing, and its tensile properties and fracture behaviour in various aging conditions were investigated. The spray deposited alloy reaches peak age condition after being aged at 190 ℃ for 20 h and obtains the best properties(σb=528 MPa, σ0.2=420 MPa , δ=12%). Fracture surface of the as-quenched alloy is totally dimple-transgranular type, while the failure mode of the aged alloy is a mixed type with intergranular and transgranular fracture. The volume of intergranular fracture increases with the aging time. The intergranular fracture is caused by planar slip of dislocations, the formation of PFZs and equilibrium phases along grain boundary.