厚钢板激光多次扫描弯曲成形的研究

采用数值模拟和实验研究分析了厚钢板激光多次扫描弯曲成形过程中弯曲角度与激光扫描次数之间的关系。建立三维热力耦合有限元模型计算了成形过程的温度场、应力场和弯曲角度的变化,对不同厚度钢板的激光多次扫描弯曲成形过程进行了实验研究,模拟结果与实验结果符合较好。在相同的工艺参数条件下,钢板越厚,弯曲角度越小。钢板弯曲角度随激光扫描次数的增加而增大,但对不同厚度钢板,它们的变化规律不同。钢板下表面的应变强化是多次扫描过程中随扫描次数增加而弯曲角度增量减小的主要原因。

Study on Multiple-irradiation Laser Bending Process of Thick Steel Plate

Numerical simulation and experimental investigation of multiple--irradiation laser bending process of thick steel plate were presented. The relationship between bending angle and the number of irradiations was investigated. A three--dimensional coupled thermo--mechanical FEM model was developed to calculate the temperature field, stress field and bending angle. An experimental study was performed for different thickness. The simulation results compare well with the experimental ones. The bending angle is small for the thicker steel plate at the same process parameters. The bending angle is increased with the increase of laser scanning passes. But the relationship between bending angle and the number of irradiations is different for the different thickness. The strain hardening effect on the underside of the sheet is the main reason for the decaying increase in the bending angle with an increasing number of irradiations.