节约金属的重要方法之一是延长机器的使用寿命.在机器使用过程中,大多数情况下零件不能再使用的原因是尺寸发生变化,产生这个变化的原因是零件表面被磨损,浸蚀、氧化等,或者由于这些原因造成表面不光滑,因此降低零件的耐疲劳强度或耐冲击强度而遭到破 One of the important ways to save the metal is to extend the service life of the machine.In the process of using the machine, the part can not be reused in most cases because the size changes, the reason for the change is that the surface of the part is worn, eroded, oxidized Etc., or because of these reasons, resulting in the surface is not smooth, thus reducing the fatigue resistance of parts or impact strength was broken