不同光束移动速度下的激光淬火有限元分析

FEM analysis of laser hardening with different laser moving velocities

为研究不同激光淬火处理条件下激光淬火温度场和物相结构,运用ABAQUS/Standard对激光淬火处理AISI4140钢进行了有限元模拟,并结合实验进行了验证.结果表明:激光淬火材料最高温度并不在光束中心,而是出现在距激光束中心2 mm的位置,且不随着光束移动速度的增大而改变位置;在激光束最高温度恒定为1150℃情况下,不同移动速度对于升温速率影响更加显著,而降温速率则相对稳定;材料本身性质和热边界条件是影响降温速率的主要因素,激光束移动速度为次要因素.另外,可以通过此模型制定合理激光处理工艺得到相应深度马氏体硬化层.

To investigate the temperature field and phase distribution in laser hardening with different laser moving velocities,the simulation of laser hardening process for AISI 4140 was carried out using finite element analysis software ABAQUS/Standard and the simulated results were verified by corresponding experimental results.The results showed that the maximum temperature position on laser hardening treated surface did not appear at the center of laser beam but 2 mm behind the center and the maximum temperature position did not change with the increasing of laser moving velocity.The change of laser moving velocity influenced heating rate more significant than cooling rate and the cooling rate was relative stable when laser moving velocity change.The main affecting factor on cooling rate was the property of material and the thermal boundary condition,the secondary factor was laser moving velocity.Additionally,using this model could establish reasonable parameters to obtain any depth of martensitic hardened layer.