摘要
采用电子束选区熔化技术制备Nb521合金,研究其致密化成形工艺。通过对成形试样的组织、物相、显微硬度、室温拉伸性能的检测与分析,探讨了电子束选区熔化成形Nb521合金的机理。结果表明,电子束选区熔化成形过程中,电子束熔化电流及速度的合理匹配,是得到表面质量及内部质量优异的成形样品的基础;电子束能量密度为340 J/mm 3时,样品的密度达到8.78~8.79 g/cm 3;Nb521合金显微组织沿沉积方向呈柱状晶,晶粒沿(200)晶面有较强的择优生长取向;成形样品中除Nb基体相外,还存在少量的Nb 2 C与ZrC碳化物析出;样品室温抗拉强度达到384 MPa,屈服强度为307 MPa,断后延伸率为16.5%;显微硬度处于1500~1700 MPa之间,无各向异性。
The Nb521 alloy was fabricated by selective electron beam melting to investigate the densification properties.The microstructure,phase,micro-hardness and room temperature tensile properties of the as-build niobium tungsten alloys were tested and analyzed,and the mechanism of selective electron beam melting of Nb521 alloy was also discussed.The results show that the reasonable matching of electron beam melting current and velocity is the basis for obtaining the samples with excellent surface quality and internal metallurgical quality.When the energy input density is 340 J/mm 3,the density of the sample can reach 8.78~8.79 g/cm 3.The microstructure of Nb521 alloy along the deposition direction presents columnar crystal characteristics,X-ray analysis shows a strong preferential growth on the(200)plane.The phase analysis of the formed samples shows that in addition to the Nb matrix phase,there are still a small amount of precipitates calibrated as Nb 2 C and ZrC.The tensile strength of Nb521 alloy at room temperature is 384 MPa,the yield strength is 307 MPa,and the elongation is 16.5%.The hardness shows no anisotropy with a hardness of 1500~1700 MPa.
作者
李会霞
朱纪磊
车倩颖
赵培
赵小欢
弋阳
刘彬
Li Huixia;Zhu Jilei;Che Qianying;Zhao Pei;Zhao Xiaohuan;Yi Yang;Liu Bin(Xi’an Sailong Metal Materials Co.,Ltd.,Xi’an 710018,China;State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China)
出处
《钛工业进展》
CAS
北大核心
2020年第4期35-40,共6页
Titanium Industry Progress
基金
广东省重点领域研发计划项目(2019B090904001)
粉末冶金国家重点实验室开放课题资助(2020DWKF002)。
关键词
电子束选区熔化
增材制造
铌钨合金
致密化
selective electron beam melting
additive manufacturing
niobium tungsten alloys
densification
