在大多数情况下,外部摩擦对塑性变形的行程有不良的影响。采用人工润滑变形材料和工具工作表面的方法可以减少摩擦的不良影响。对金属进行压力加工时,一般按照下列要求选择润滑剂; In most cases, external friction has a detrimental effect on the stroke of plastic deformation. The use of artificial lubrication of deformed materials and tooling surfaces can reduce the adverse effects of friction. Pressure on the metal processing, the general requirements in accordance with the following selection of lubricants;