Many parts such as bathroom accessories, kitchen utensils, locks, lighting accessories, etc. are produced by investment casting. Usually, the shapes of these metal parts are relatively complex, and the required precision is relatively high. The use of investment casting technology to produce these parts is highly efficient and relatively inexpensive. Moreover, it can be produced in small or large batches, which has great advantages over other production processes. In addition, the materials available for investment casting are also more extensive. Commonly used carbon steel, stainless steel, alloy steel, etc. can be used as raw materials for investment casting, so each metal part can choose the appropriate material according to the environment or use requirements.