铜带连续挤压两次扩展成形力学模型

Research on mechanical model of continuous extrusion with two-step extending forming for copper strip

以TLJ500连续挤压机为模型,将具有两次扩展成形的连续挤压型腔划分为3个变形区,利用上限法建立各分区挤压力的力学模型,得出扩展腔入口单位挤压力与产品断面尺寸、形状复杂系数的关系。结果表明,对于一定的腔体结构,在产品厚度一定时,产品宽度与扩展腔入口挤压力呈线性关系,即挤压力随产品宽度的增加而增加;在产品宽度一定时,扩展腔入口挤压力随产品厚度的减小而增加,当厚度<12mm时,挤压力随着产品厚度的减小急剧增加;扩展腔入口挤压力随着产品形状复杂系数的增加而增加。

Based on the model of continuous extrusion machine TLJ500,the continuous extrusion extending cavity was divided into first extending region,second extending region and deformation region.The upper bound method was used to establish the dynamic models of extrusion force for each region,and the correlation between the specific extrusion force at the inlet of extending cavity with the section size of the part and shape complicated coefficient was derived.The result shows that for definite cavity structure,when the product thickness keeping constant,the extrusion force at the inlet of extending cavity increases with the increase of product width;when the product width keeping constant,the extrusion force at the inlet of extending cavity increases with the increase of shape complicated coefficient and the decrease of product thickness,and would increase sharply when the thickness is less than 12mm.