连续挤压与正挤压在扩展成形中的对比分析

Contrast analysis of extending forming between continuous extrusion and forward extrusion

通过有限元数值模拟分析了连续挤压较常规正挤压更能实现铜的更大扩展比挤压的原理。在连续挤压扩展模型的基础上建立了与之相对应的常规正挤压模型,对两种模型下金属的流动特性进行了对比分析。连续挤压与正挤压相比,由于在挤压轮槽区,受到挤压轮三面的主动摩擦力和腔体一面阻碍摩擦力的作用,有利于提高铜扩展成形金属流动的均匀性;而正挤压中坯料在挤压筒区受四面的摩擦阻力的作用,加剧了金属流动的不均匀性。所以,连续挤压中的扩展成形金属在产品宽度和厚度方向上流动较正挤压更均匀,成形产品的完整性更好。因此,连续挤压更利于铜的扩展成形。

The principle of the bigger ratio of copper extending obtained by continuous extrusion compared with forward extrusion was analyzed by finite element method. The forward extrusion model was built based on the continuous extrusion model. Then the flow characteristics contrast was carried out. In continuous extrusion, the metal in groove was under the action from three sides initiative friction and one side resistance friction, and it could improve the uniformity of metal flowing. In forward extrusion, the metal in container was in four-side resistance friction, and it could aggravate the nonuniformity of metal flowing. So in the thickness and width direction of product, the metal flowing is more uniformity during the continuous extrusion, and the integrality of product is finer. The continuous extrusion is propitious to the copper extending forming.