腔体结构对连续挤压金属流动的影响

Effect of chamber structure on metal flowing in continuous extrusion

以一次扩展腔、二次扩展腔的通道长度、进料口高度及二次扩展角4个腔体主要参数为研究对象,通过正交试验,设计9组腔体结构。基于DEFORM-3D软件平台,对上述腔体结构的铜带坯连续挤压过程进行数值模拟,以模口处金属流速标准偏差为指标,通过极差分析,得到利于金属流动的最优腔体结构,该结构能够降低金属流动速度差,提高产品成形质量。最优腔体结构温度场的数值模拟结果表明,最优腔体结构的温度合理,有利于延长工模具寿命;对最优腔体及其余两种腔体结构的挤压成形过程进行物理模拟,结果显示,最优腔体结构的流动均匀性较其他两种腔体结构好,与数值模拟结果吻合。

Nine chamber structures were designed through orthogonal experiment design using four main chamber parameters in- cluding the first extended flow channel length, the second extended flow channel length, the height of feed opening and the sec ond extended angle. Based on DEFORM-3D software platform, the copper strip continuous extrusion processes of the above chamber structures were simulated, and the velocity standard deviation of die open was used as a criterion. By range analysis, the optimized chamber structure was obtained which can reduce the velocity difference of metal flowing and improve the forming quality. The temperature field of the optimized chamber was analyzed by numerical simulation, and the results showed that the temperature of the optimized chamber is reasonable for prolonging the service life of the tools. The physical simulations of the ex- trusion forming for the optimal and other two chamber structures showed that the flow uniformity of the optimal structure was better than other two chambers, which agreed with the numerical simulation results.