汽车蓄能器储压管成形过程的数值模拟

Numerical simulation of the forming process for pressure accumulating tube in automobile accumulator

在分析汽车蓄能器储压管成形工艺的基础上,采用刚粘塑性热力耦合有限元技术,以成形载荷为评定标准,用Deform-3D软件对影响成形的坯料温度、模具预热温度、凸模速度3个工艺参数进行正交试验模拟分析。通过试验最终得到最佳成形工艺为:温挤压坯料温度850℃,模具预热温度300℃,凸模下压速度16 mm·s-1;冷挤压凸模速度8 mm·s-1。模拟结果表明,在该制件成形过程中,温挤压坯料温度和凸模速度对成形载荷影响最大,模具预热温度影响相对较小,但为了减少温差对成形的影响,模具预热温度应选取相对较高的温度;在后续冷挤压中应选取较小的凸模速度。按照该工艺参数进行实际零件的挤压生产,最终得到了符合要求的成形零件。

Based on the analysis of the forming process for pressure accumulating tube in automobile accumulator, the application of rigid viscoplastic finite element technology and the evaluation standard of the forming load, three technological parameters （billet temperature, die preheating temperature and punch speed） influencing the forming process were simulated and analyzed through the orthogonal experiments by Deform-3D software. The optimal technological parameters obtained from experiments are billet temperature 850 ℃, die preheating temperature 300 ℃, punch speed downwards 16 mm · s^-1 during the warm extrusion process and punch speed 8 mm · s^-1 for cold extrusion. The numerical simulation results show that both the temperature of warm extrusion billet and punch speed have great effects on forming load, while the effect of die preheating temperature is relatively small. In order to reduce the effects of temperature on the forming process, the preheating temperature for the die should be relatively high temperature ; and then during the cold extrusion, the punch speed should be relatively small. As a result, the qualified forming parts were obtained from actual extrusion with above parameters.