预约束应力作用下的激光弯曲成形仿真工艺研究

提出了一种预约束应力作用下的激光弯曲成形新工艺 ,研究了不同的加载模型 ,通过施加预载荷 ,使板料加热区材料产生期望的预应力分布。针对激光弯曲成形的特点 ,建立了三维热力耦合模型 ,采用有限元方法实现了预约束应力作用下的激光弯曲成形工艺过程仿真。分析了在预载荷作用下 ,板料的激光弯曲成形机理。研究表明 ,该工艺不仅可大大提高板料的弯曲成形效果 ,而且只要合理控制预载荷的方向和大小 ,即可控制激光弯曲成形的变形方向。板料弯曲角度随预载荷的增加而显著增大 ,两者呈指数关系

Simulation of the Laser Bending Process of Sheet Metals with Pre-stresses

A new laser bending process of sheet metals with pre stresses is put forward. The different loading models are analyzed, and desired pre stress distribution in heated zone of the sheet is acquired. The three dimensional thermo mechanical model is established. Using the thermal elastic plastic finite element method (FEM), the process is simulated numerically. Its forming mechanism is analyzed. The bending angles of the sheet metals can be improved significantly, and the deformation direction can also be controlled easily by changing the direction and value of the pre load reasonably. The bending angles of the sheet metals augment remarkably with the improvement of the pre load, and both are in exponential relationship.