Precision machining is a process that alters the shape, size, or performance of workpieces using processing machinery. Depending on the temperature state of the workpiece being processed, it is divided into cold working and hot working. Generally, cold working is performed at room temperature and does not cause chemical or phase changes in the workpiece. Hot working, typically carried out at temperatures above or below room temperature, can induce chemical or phase changes in the workpiece. Cold working can be further classified into cutting and pressure processing. Hot working commonly includes heat treatment, forging, casting, and welding.