5A06铝合金交叉筋壁板激光诱导自由成形扭曲现象研究

针对交叉筋壁板激光成形后的整体扭曲变形现象,采用相应的校正方法对板材进行了校正,并利用有限元分析进行了研究。研究表明交叉筋壁板激光成形后出现的整体扭曲现象是由板材中部加强筋侧倾失稳造成的,提出板材扫描线不同部位协同变形为成形的关键并提出了协同变形扫描方式。针对协同变形扫描方式消除板材整体扭曲变形的现象进行了有限元分析,结果显示采用协同变形扫描方式后板材中部蒙皮所受到的约束减小,产生的拉应力减小,从而减小了对中部加强筋的压缩,消除了中部筋的侧倾失稳,最终避免了交叉筋壁板激光成形后的整体扭曲现象。

The Study of the Twisting Phenomenon of Panel with Crossed Reinforcing Bars under Laser Forming Technology

In actual laser forming process, integral twisting phenomenon would take place on panels with crossed reinforcing bars. Corresponding corrective measures are adopted. According to the analysis and the experiments, the reason of integral twisting phenomenon can be explained as Lateral-torsional buckling of the middle stiffener. The experiments show that the consistency of the deformation along the scanning line is the key to the bending of the panel and the consistency-deformation scanning strategy (CDSS) is proposed. The finite element analysis of the panel formed with the CDSS indicate that after being processed with the CDSS, the residual tensile stress of the plate around the middle stiffener decreases, which results in the decrease of the compressive stress of the middle stiffener. The lateral-torsional bulking of the middle stiffener and the twisting of the panel are avoided homologously. Finally the integral twisting of crossed reinforcing bars can eliminated through CDSS.