激光扫描搭接区内的热循环与应力变化规律分析

详细信息

Analysis on the variation principle of thermal cycle and stress in the laser overlapping area

1.
Key Laboratory of Advanced Manufacturing Technology, Beijing University of Technology, Beijing 100022, China;
2.
Mechanical Department, Tangshan Institute, Tangshan 063000, China;
3.
BOE Corporation, Beijing 100016, China

摘要: 由于搭接扫描的影响,激光扫描带内的不同区域之间存在着硬度落差,并且搭接区极易出现裂纹。通过数值模拟方法可以精确给出光束移动过程中搭接区内的温度和应力变化规律,从而给出激光扫描形成回火区和二次淬火区的理论解释。仿真结果表明,选取不同的搭接参数对于该区域的温度变化规律影响不大,但从改善表面硬度不均和搭接区裂纹的角度出发,搭接参数不宜过大。
- 激光强化 /
- 搭接区 /
- 热循环 /
- 残余应力
Abstract: It is unavoidable that the hardness in the laser scanning area is not uniform due to the laser overlapping.Furthermore,the crack is apt to appear in the overlapping area.Firstly,the varying principles of the thermal cycle and stress during the laser scanning can be explained through the numerical methods.As a result,the theoretical explanations of the formation of the tempering and second quenching area are shown.The simulation results indicate that different overlapping parameters have little influence on the temperature varying principles.On the other hand,the parameters should not set too large in order to reduce the ununiformity of the hardness and crack in the area.
- laser strengthening /
- overlapping area /
- thermal circulation /
- residual stress

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