激光重熔处理对铸态Zn-27%Al合金的组织和性能的影响

MICROSTRUCTURE AND PROPERTIES OF AS-CAST Zn-27%Al ALLOY AFTER LASER REMELTED REPCESSUBG

经激光表面重熔处理后高铝锌基铸态Ｚｎ－２７％Ａｌ合金的表层组织结构和性能均发生了较大的变化。表层组织根据其组织形态特征可分为非树枝状晶区、树枝状晶区和半熔化区三层。与激光处理前的相比，在Ｘ射线衍射谱上个η－Ｚｎ相衍射强度降低，α－Ａｌ相衍射峰出现边带效应。表层硬度和耐磨性由于组织细化而分别提高了约１５％和２６％。若提高激光加热功率，硬化层深度随之增加。

Microstructure and properties of the surface layer of a laser - remelted - treated as - cast Zn - 27% Al alloy are changed. The layer can be divided into non-dendrite, dendritel and partly- melted zones according to the features of the microstructure. Diffraction intensity ofη - Zn phase decreased and hinge effect appeared in the diffraction peakes of a -Al phase on X - ray spectrometer after the alloy is treated, and hardness of the layer surface and wear resistance are increased respectly 15% and 26% because of a very fine microstructure of the layer comparing with ones of the original alloy. The depth of the hardened layer increases with the increment of laser heating power.