A tool for making a blank into a product with a specific shape and size under the action of external force. Widely used in blanking, forming stamping, die forging, cold heading, extrusion, powder metallurgy parts pressing, pressure casting, compression molding or injection molding of engineering plastics, rubber, ceramics and other products. The mold has a specific contour or cavity shape, and by applying the contour shape with cutting edge, the blank can be separated (punched) according to the contour shape. Applying the shape of the inner cavity can make the blank obtain the corresponding three-dimensional shape. Generally speaking, molds include a moving mold and a fixed mold (or a male mold and a female mold), which can be separated or combined. When separating, the blank is loaded or the workpiece is taken out, and when closing, the workpiece and the blank are separated or formed. Die is a kind of precision tool with complex shape, which bears the bulging force of blank and requires high structural strength, stiffness, surface hardness, surface roughness and machining accuracy. The development level of mold production is one of the important symbols of the level of mechanical manufacturing. There are many kinds of molds, which can be divided into: ① molds used to process metal according to the processing object and processing technology. Including stamping die (such as punching die, bending die, drawing die, hole turning die, shrinkage die, undulating die, bulging die, shaping die, etc.). ), forging die (such as die forging die, upsetting die, etc. ), extrusion die and die casting die, etc. (2) Machining nonmetallic and powder metallurgy molds. Including plastic molds (such as injection molds, compression molds and extrusion molds, etc.). ), rubber mold and powder metallurgy mold, etc. According to the structural characteristics, the die can be divided into plane blanking die and cavity die with space. Generally, molds are single-piece and produced in small batches. In addition to the mold itself, it also needs a mold base, a mold base, a guide device and a workpiece ejection device, which are generally made into universal types.

Classification According to the different molding materials, molds can be divided into metal molds and non-metal molds. Metal molds are divided into: casting molds (non-ferrous metal die casting, steel castings), stamping molds and forging molds; Non-metallic molds are divided into plastic molds and inorganic non-metallic molds. According to the different materials of the mold itself, the mold can be divided into sand mold, metal mold, vacuum mold, paraffin mold and so on. Among them, with the rapid development of polymer plastics, plastic molds are closely related to people's lives. Generally, plastic molds can be divided into injection molds, extrusion molds and gas-assisted molding molds. Mass production of non-sheet metal steel parts-cold heading, die forging, metal die, etc. Sheet metal discharging-hot rolling, cold rolling, hot rolling and cold rolling sheet metal processing-stretching, forming, bending, punching, blanking non-ferrous metals-die casting, powder metallurgy plastic parts-injection molding, blow molding (plastic bottles), extrusion (pipe fittings) molds Other categories: alloy molds, sheet metal molds, plastic molds, stamping molds, rubber molds, casting molds, etc.