摘要
采用粉末等离子堆焊方法,对自制的C-Cr-Nb-Ni合金粉末进行堆焊,研究了不同堆焊电流对熔深的影响。对堆焊层进行显微硬度测试,采用金相显微镜和扫描电镜分析了堆焊层的显微组织及物相。研究结果表明,堆焊电流120 A时,母材基本不发生熔化,可得到低稀释率的堆焊层。堆焊层的显微硬度在距熔合线0.5 mm以后,硬度增加不明显。堆焊层的显微组织主要为马氏体及少量残余奥氏体,硬质相为六边形状Cr3C2,熔敷层碳含量和铌含量较高,但并未形成铌的碳化物,含铌化合物起到形核质点及细化晶粒的作用。
C-Cr-Nb-Ni alloy powder was deposited with powder plasma arc overlaying welding. The effects of welding current on the penetration were studied. The microhardness test was carried out. The microstructure and phase was analyzed by using metallographic microscope and SEM. The research results show that when the welding current do not exceed 120A, the base metal does not melt and the deposited joint has low rate of dilution. The microhardness of deposited metal increase slowly with the distance away from fusion line. The microstructure of deposited metal is mainly martensite and retained austenite. The hard phase is Cr3C2 with hexagon shape. Although the carbon content and niobium content in the deposited metal is high, the niobium carbide is not formed. The compound containing niobium can act as nucleation point, which can refine the grain crystal.
出处
《热加工工艺》
CSCD
北大核心
2014年第23期196-198,共3页
Hot Working Technology
基金
先进焊接与连接国家重点实验室开放课题研究基金资助(AWJ-M13-01)
关键词
粉末等离子堆焊
浅熔深
熔敷层性能
powder plasma arc overlaying welding
low penetratiori
properties of deposited metal
