时效处理对挤压成型2195铝锂合金组织和力学性能的影响

Effect of aging treatment on microstructure and mechanical properties of extruded 2195 Al-Li alloy

研究了热处理对挤压态2195铝锂合金组织和力学性能的影响。结果表明,固溶处理和人工时效处理对挤压合金的力学性能有显著的增强作用,这与析出相的类型、尺寸、数量密度和分布有关。2195铝锂合金在时效过程中的析出顺序为过饱和固溶体(SSSS)→GP区+δ′/β′(Al_(3)(Li,Zr))→δ′+θ′(Al_(2)Cu)+T_(1)(Al_(2)CuLi)→θ′+T_(1);其中T_(1)相在析出强化中起主导作用。2195铝锂合金经过525℃×60 min固溶后在170℃人工时效的峰时效时间是36 h,此时抗拉强度、屈服强度和伸长率分别为579 MPa、537 MPa和5.5%。

Effect of heat treatment on microstructure and mechanical properties of as-extruded 2195 Al-Li alloy was investigated.The results show that the mechanical properties of the as-extruded alloy can be significantly enhanced by solution treatment and artificial aging treatment,which is related to the type,size,number density and distribution of precipitated phases.The 2195 Al-Li alloy precipitation sequence during the aging process is SSSS(supersaturated solid solution)→GP zone+δ′/β′(Al_(3)(Li,Zr))→δ′+θ′(Al_(2)Cu)+T_(1)(Al_(2)CuLi)→θ′+T_(1).The T_(1) phase plays a leading role in precipitation strengthening.After solution treatment at 525℃for 60 min and artificial aging at 170℃,the peak aging time of the 2195 Al-Li alloy is 36 h,under which the tensile strength,yield strength and elongation are 579 MPa,537 MPa and 5.5%,respectively.