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为了研究高斯脉冲激光的表面热处理机理以及相变硬化机理,本文采用傅立叶传热方程以及自定义高斯脉冲热源项建立了轮毂局部热处理有限元模型,并分析了在高斯脉冲激光作用下轮辋等温线分布规律。结果表明:轮毂热处理的最高温度出现在脉冲激光热源附近,其温度达到铝合金的奥氏体转变温度,随着材料迅速冷却,轮毂表面结构由奥氏体组织转变为马氏体组织;由于脉冲激光的空间非连续加热特性,在热处理过程中轮毂整体温度明显低于熔点,从而避免了轮毂表面局部熔化;轮毂厚度方向上的温度梯度较大,轮辋最大温度呈波峰波谷形式波动,而最低温度逐渐增大。
In order to study the surface heat treatment mechanism and phase transformation hardening mechanism of Gaussian pulsed laser, a finite element model of local heat treatment of hub was established by Fourier heat transfer equation and self-defined Gaussian pulse heat source. The distribution of rim isotherms under Gaussian pulsed laser was analyzed law. The results show that the maximum temperature of the hub heat treatment occurs near the pulsed laser heat source and the temperature reaches the austenite transformation temperature of the aluminum alloy. As the material rapidly cools, the surface structure of the hub changes from austenite to martensite; In the process of heat treatment, the overall temperature of the hub is obviously lower than the melting point, thereby avoiding local melting of the hub surface. The temperature gradient in the direction of the hub thickness is larger and the maximum temperature of the rim fluctuates in a wave trough. The minimum temperature Increasingly.