摘要
目的针对205B增材制造成形件存在组织均匀性差、强度低和力学性能各向异性大等缺陷问题,对其进行了热处理以期改善合金的相关性能。方法以激光-电弧(CMT)复合增材205B铝合金为研究对象,采用固溶淬火+时效热处理的研究方法,对不同热处理工艺下材料的宏微观组织形貌、第二相分布、显微硬度及拉伸强度进行表征。结果随固溶时间的延长,晶界处α+θ共晶组织逐渐消失,Cu元素固溶到Al基体中;当固溶时间为120 min时,材料的显微硬度、横向和纵向平均拉伸强度分别为152.48HV、439.51 MPa、429.15 MPa。随时效时间的延长,晶内T相不断长大和聚集,并形成“黑色块状物质”;且试样的显微硬度、横向和纵向拉伸强度均随固溶时间的延长呈现出先上升后下降的趋势,当时效时间为360 min时,材料获得了最佳的力学性能(硬度154.67HV、横向拉伸强度448.05 MPa、纵向拉伸强度435.59 MPa)。结论采用固溶淬火+时效热处理的方法能有效改善复合增材205B铝合金宏微观组织的均匀性,且能大幅提高其硬度并降低拉伸强度的各向异性。
The work aims to conduct heat treatment on additively formed parts of 205B aluminium alloy of poor tissue uni-formity,low strength and large anisotropy of mechanical properties,so as to improve the properties of the alloy.Solid solution quenching+aging heat treatment method was adopted and the macro-microstructure morphology,second phase distribution,mi-cro-hardness and tensile strength of laser-arc(CMT)composite additive 205B aluminum alloy under different treatment pro-cesses were characterized.With the increase of solid solution time,theα+θeutectic organization at the grain boundary gradually disappeared,and the Cu element was solidly dissolved into the Al matrix;When the solid solution time was 120 min,the mi-cro-hardness,transverse tensile strength,and longitudinal tensile strength of the material were 152.48HV,439.51 MPa,and 429.15 MPa,respectively.With the prolongation of aging time,the T-phase in the crystal continued to grow and aggregate,forming“black lumps”;The micro-hardness,transverse tensile strength and longitudinal tensile strength of the specimen showed a trend of first increasing and then decreasing with the increase in solid solution time.When the aging time is 360 min,the ma-terial obtained the best mechanical properties(hardness of 154.67HV,transverse tensile strength of 448.05 MPa,longitudinal tensile strength of 435.59 MPa).The use of solid solution quenching+aging heat treatment method can effectively improve the macro-microstructure uniformity of 205B aluminum alloy obtained by composite additive and can significantly increase its hardness and reduce the tensile strength anisotropy.
作者
牛晨旭
张嘉
吕蒙
郭海伟
杨丰豪
NIU Chenxu;ZHANG Jia;LYU Meng;GUO Haiwei;YANG Fenghao(Zhengzhou Railway Vocational and Technical College,Zhengzhou 451460,China;Zhengzhou Key Laboratory of Advanced Functional Materials,Zhengzhou 450007,China;Zhengzhou Nonferrous Metals Research Institute Co.,Ltd.,of CHALCO,Zhengzhou 450041,China)
出处
《精密成形工程》
北大核心
2025年第6期187-196,共10页
Journal of Netshape Forming Engineering
基金
河南省科技攻关项目(232102231011,222102230025)
河南省教育厅高等学校重点科研项目(23B430016)。
