基于水冷却的不锈钢板料激光热应力成形试验

Study on Laser Forming of AISI304-sheet Metal by Thermal Stress Based on Water-cooling

通过改变激光束能量、光斑直径、扫描速度、扫描次数以及板材厚度对AISI304不锈钢板料进行弯曲试验,分析了在水冷却条件下各工艺参数对弯曲变形的影响,探讨了基于水冷却的板料热应力成形规律,并通过正交试验对相关工艺参数进行了优化。试验结果表明:0.6mm厚度的不锈钢板在线能量密度小于80J/mm时,工件不产生变形;在150～180J/mm范围内,热应力成形的效果最佳;扫描次数、光斑直径以及板材厚度对弯曲变形的影响较大。同时对水冷却条件下工件表面烧蚀及成形稳定性进行评估,提出了基于水冷却的板料激光热应力成形的新工艺,为精确控制板料激光热应力成形提供了试验基础。

Technological parameters such as laser beam energy, laser spot, scanning velocity, scanning times, scanning path and thickness of sheet metal were varied in the test of AISI304-sheet metal bending with thermal stress induced by laser. Comparative analysis has been done on the effects of different process parameters in bending test under the condition of water-cooling, and the relationships were discussed. At the same time, the orthotropic experiment has been done to optimize the interrelated parameters. The results showed that there was no bending for 0. 6 mm thickness of AISI304-sheet steel under the condition of water cooling when linear energy density was less than 80 J/mm; the best value of the linear energy density was between 150 and 180 J/mm for it; the technological parameters such as the thickness of sheet metal, laser spot and scanning times have greatly effect on the bending angle. And the ablation and stability of bending for AISI304-sheet metal in the experiment has been evaluated as well. The new idea of sheet forming by laser thermal stress based on water-cooling was put forward, which provided the experimental foundation to accurately control the sheet forming by laser induced thermal stress.