摘要
采用脉冲激光对纯 Fe、纯 Ni、20钢和 Ni 基合金进行了快速熔凝处理。结果表明,在纯 Fe和纯 Ni 熔凝区内,生成了一种外延生长的晶粒组织;在20钢和 Ni 基合金熔凝区内,生成了外延生长晶粒和极细的枝晶组织。在金属与合金的熔区中均形成了精细的的亚晶粒。激光快速熔凝大大地细化了校晶和亚晶,却没有得到明显细化的晶粒。
Laser rapid solidification treatment on pure Fe,20 steel andNi-base alloy is performed by means of pulse laser.The results show thatsome epitaxially growing grains are formed in the melted zones of pure Fe andNi.The epitaxially growing grains and fine dendritic microstructures are formedin the 20 steel and Ni-base alloy.Meanwhile,a large amount of fined sub--grains appear in the melted zones of the metals and the alloys.The epitaxiallygrowing grains in laser melted zones are not fined,but the dendritic micros-tructures and sub-grains are fined greatly.
关键词
金属
激光
快速
熔凝
表面处理
laserglaze
epitaxial growth
dendritic refine
sub-grainL
heterogeneously nucleated temperature gradient
