化学反应热效应对激光熔凝区几何特征的影响

Influence of calorific effect of chemical reaction on geometric characteristics of laser remelting zone

为了研究附加化学反应热的激光熔凝区特征,采用在低合金钢表面预制Mg,Al和Fe3O4涂层进行激光处理,得到了化学反应热影响激光熔凝区形貌的实验结果。结果表明,引入化学反应热源,使激光熔化区宽度、热影响区宽度和深度增加,熔化区的深宽比降低;Al和Fe3O4涂层的熔化深度比表面黑化处理的熔深深,Mg和Fe3O4涂层的熔化深度比表面黑化处理的熔深浅;利用多元合金氧化物还原化学反应热和激光形成复合热源,可以快速形成多元合金共渗的熔凝层。

In order to study the geometric characteristics of laser remelting zone was additional chemical reaction heat,the experiments of laser cladding with a CO2 laser were conducted by prefabricated coating of Al or Mg and Fe3O4 on the surface of low alloy steel, the effects of chemical reaction heat on morphology of laser remelting zone were obtained. The results show that the chemical reaction heat makes the increase of the width of laser remelting zone and heat-affected zone, and the decrease of the depth-to-width ratio of laser remelting zone. The melting depth adding Al and Fe3O4 coating is larger than that of blackened surface, and the melting depth adding Mg and Fe3O4 coating is lower than that of blackened surface. The multi-component alloy permeating layer may be formed quickly in laser remelting zone by means of multi-component reducing reaction of alloying oxidate.