激光选区熔化成形GH4099合金高温拉伸性能研究  

Study on High-temperature Tensile Properties of GH4099 Alloy Formed by Laser Selective Melting

作　　者：崔哲 杨帆 杜磊 付言飞 肖美立[1] 柯林达[1] CUI Zhe;YANG Fan;DU Lei;FU Yanfei;XIAO Meili;KE Linda(Shanghai Spaceflight Precision Machinery Institute,Shanghai 201600,China)

机构地区：[1]上海航天精密机械研究所,上海201600

出　　处：《材料导报》2024年第S01期435-438,共4页Materials Reports

基　　金：国防基础科研计划(JCKY2021203A006)。

摘　　要：通过研究激光选区熔化成形GH4099合金的显微组织和强化机理,对工艺参数进行了优化,对比分析了SLM试样与冷轧板在室温、500℃、700℃、900℃的力学性能。结果表明:优化后的工艺参数下SLM试样晶粒细小、组织致密,无明显缺陷。试样XY、XZ截面的平均硬度大致相等,约为400HV,比冷轧板高8.5%~9.8%。XY方向主要是树枝晶和胞状晶交相分布,熔池顶部存在较多的胞状晶,而XZ方向试样内部主要是外延生长的柱状枝晶。室温状态下成形试样的平均拉伸强度可达1160 MPa,规定塑性延伸强度为736 MPa,断后延伸率在29.5%以上,高于冷轧板。另外三种温度下试样的力学性能也优于冷轧板。By studying the microstructure and strengthening mechanism of GH4099 alloy formed by laser selective melting,the process parameters were optimized,and the mechanical properties of SLM specimens and cold-rolled plates at room temperature,500℃,700℃and 900℃were compared and analyzed.The results show that the SLM specimens have fine grains and dense microstructure under the optimized process parameters,and there are no obvious defects.The average hardness of XY and XZ sections is roughly equal,about 400HV0.2,which is 8.5%—9.8%higher than that of cold-rolled plate.In the XY direction,dendrites and cytoplasms are mainly interphased,and there are more cytomorphic crystals at the top of the molten pool,while the inside of the XZ direction is mainly columnar dendrites grown in epitaxy.The average tensile strength of the formed specimen at room temperature can reach 1160 MPa,the specified plastic elongation strength is 736 MPa,and the elongation after fracture is more than 29.5%,which is higher than that of cold-rolled plate.The results of the mechanical properties at the other three temperatures are also better than those of cold-rolled plate.

关 键 词：激光选区熔化 GH4099合金 工艺参数 力学性能 

分 类 号：TG132.3[一般工业技术—材料科学与工程]