金属板料激光预应力复合的喷丸成形

在对激光热应力成形(LTF)和激光喷丸成形(LPF)的技术优势进行分析的基础上,提出了一种板料激光预应力复合喷丸成形技术,其将连续激光的热堆积作用和脉冲激光的冲击波作用相结合,是一种热效应和力效应复合的成形方法。板料激光预应力复合喷丸成形技术首先使用CO2激光器对2 mm厚的SUS304不锈钢板料按特定的轨迹扫描以施加预应力,实现板料基本形状成形,然后通过ATOS-Ⅱ光学扫描测量系统测量成形后板料表面的轮廓点云图,利用逆向软件Imageware建立成形板料的虚拟模型。利用有限元软件ABAQUS与逆向软件Imageware的接口,将虚拟模型转换为有限元分析模型,通过调整激光工艺参数和控制激光喷丸轨迹,模拟得到最优的残余应力场分布。然后使用数值模拟优化的激光工艺参数和喷丸轨迹进行板料激光喷丸成形实验。结果表明,经激光复合成形的板料获得预期的形状,且正反两面都呈残余压应力场分布。

Laser Pre-Stressed Compound Peen Forming of Plate

Based on the analysis of advantages on laser thermal-stress forming (LTF) and laser peen forming (LPF), a laser pre-stressed compound peen forming of plate is presented, the technology combines heat stack action of continuous laser and shock wave action of pulse laser, so it combines heating effect and mechanics effect. At first, CO2 laser is used to scan SUS304 stainless plate which is 2 mm thickness according to special tracks to apply pre-load stress, the basic configuration is formed and residual stress is measured. ATOS-Ⅱ optical scan measure system is used to measure the contours of the plate′s surface after pre-forming, the reverse engineering software Imageware is used to establish virtual model of the plate. Then the interface between ABAQUS and Imageware is used to invert virtual model into finite element model, the optimum distribution of residual stress field is obtained through adjusting laser processing parameters and controlling tracks of laser peening by ABAQUS. Finally, the optimum laser parameters and processing condition are used for laser peen forming experiment. The results indicate that the anticipated shape is obtained, and both sides of the plate hold residual compressive stress field after laser pre-stressed compound peen forming.