局部热处理差性板提高2B06铝合金口框零件成形性的模拟研究

Simulation study on improving formability of frame parts for 2B06 aluminum alloy by local heat treatment tailored heat treated blanks

通过单向拉伸试验获得2B06铝合金原始O态和短时热处理板材的力学性能参数。采用有限元模拟方法模拟并验证了局部热处理差性板材在铝合金口框零件两次充液成形中的应用,分析了零件成形能力提高的机理。模拟结果表明:采用原始O态板材成形口框零件时,局部减薄严重,破裂危险区多发生在平面应变区域;合理的局部热处理方案使得板材具有软硬材料的梯度分布,显著提高了口框零件的成形能力。通过激光实验测温装置确定激光热处理的工艺参数,对涂有水基石墨热处理区域的板材进行热处理,使其成为差性板,再对差性板进行两次液压成形,验证了模拟的准确性。

The mechanical property parameters of original O-state and short-time heat-treated sheets for 2 B06 aluminum alloy were obtained by uniaxial tensile test. Then,the application of local heat treatment tailored heat treated blanks( THTB) in the two-pass hydroforming of aluminum alloy frame parts was simulated and verified by the finite element simulation method,and the mechanism of improving the forming ability of parts was analyzed. The simulation results show that when the original O-state sheets are used to form the frame parts,the local thinning is serious,and the rupture danger zone mostly occurs in the plane strain region. Therefore,a reasonable local heat treatment scheme makes the sheet have a gradient distribution of soft and hard materials,which significantly improves the forming ability of frame parts. Furthermore,the process parameters of laser heat treatment were determined by the laser experimental temperature measuring device,and the sheet coated with the water-based graphite heat treatment zone is heat treated to make it the THTB. Finally,the THTB is hydroformed twice to verify the accuracy of the simulation.