论文部分内容阅读
本文叙述了用钕脉冲激光加热的 T1高速工具钢的金相(光学显微镜、透射电镜、扫描电镜)、光谱和显徽硬度之研究。在激光熔化区,观察到了马氏体,残余奥氏体、6一铁素体、M_6C 碳化物以及 W、V 和 Cr 的胞状偏析。由于钕脉冲辐射与较小体积熔化材料之间为短时的相互作用,因此熔化区有高的冷却速度,从而使之获得高度化学均匀性和细小的组织。回火期间在熔化区中形成了细小的沉淀物、胞状 M_6C 碳化物和片状 MC碳化物。观察到激光熔化区的显微硬度是随回火温度的升高而增大,这归因于这些沉淀物的形成以及残余奥氏体的转变。
In this paper, the metallographic (optical microscope, transmission electron microscope, scanning electron microscope), spectroscopy and apparent hardness of T1 high speed tool steel heated by neodymium pulse laser are described. In the laser melting zone, martensite, retained austenite, 6-ferrite, M-6C carbides and cellular segregation of W, V and Cr were observed. Due to the short-term interaction between the neodymium pulse radiation and the smaller volume of molten material, the melt zone has a high cooling rate, resulting in a high degree of chemical homogeneity and fine texture. During tempering, fine precipitates, cellular M_6C carbides and lamellar MC carbides were formed in the melting zone. It was observed that the microhardness of the laser melt zone increased with the tempering temperature due to the formation of these precipitates and the transformation of the retained austenite.