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 processing and hot processing. Generally performed at room temperature and does not cause chemical or phase changes in the workpiece, it is referred to as cold processing. Typically carried out at temperatures above or below room temperature, which can cause chemical or phase changes in the workpiece, is called hot processing. Cold processing can be further divided into cutting and pressure processing based on the method of processing. Hot processing commonly includes heat treatment, forging, casting, and welding.