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With the development of metal stamping stretching technology, the market demand for metal stretching is increasing, and the requirements for products such as shape, performance, and appearance are also increasing. The metal stretching process is a processing process that uses a mold to press a certain shape of flat blank obtained after punching into various open hollow parts, or to reduce the open hollow blank to the diameter, thereby increasing the height. By using the drawing process, it is possible to create thin-walled parts with irregular shapes such as gun barrels, stairs, tapers, spheres, boxes, and other irregular shapes. It can also be used in conjunction with other stamping processes such as flanges, expansion, flares, and contraction to create very complex parts.

The tensile performance of metal materials depends on the characteristics of the material itself (such as chemical composition, microstructure, etc.), but the results obtained by the same material in different tensile experiments may also be different. There are many factors that affect the tensile properties of metals, which can be generally divided into two main aspects: the properties of metal raw materials and the impact of processing on the tensile properties of metal materials.

The influence of the properties of metal raw materials on the tensile properties of metals:

Metal materials are a general term for materials with metallic properties, usually composed mainly of metal elements or metal elements, mainly including pure metals, special metals, alloys, intermetallic compounds of metal materials, etc. During the processing of metal materials, their microstructure is affected to a certain extent and changes accordingly. The special properties of metal materials are mainly manifested in the following aspects: 1. Many metal materials need to be subjected to alternating current loads during their working process. Under this action, the yield limit of metal materials is much higher than the stress level. However, after long-term stress cycling, brittle fracture phenomena may suddenly appear. This phenomenon is the most common and dangerous form of fracture in metal material fatigue. 2. The ability of metal materials to withstand permanent deformation without damage under external loads is the plasticity of the metal material. The better the plasticity of metal materials, the more plastic deformation can be formed within a larger range. During the plastic deformation process, the strength of metal materials is strengthened, and the safety of metal materials is improved. 3. Hardness mainly refers to the resistance of metal materials that press hard objects onto the surface, and is one of the important indicators for considering the performance of metal materials. The hardness of metal materials is the result of the combined effect of initial plastic deformation resistance and continuous plastic deformation resistance. Generally speaking, the higher the hardness of metal materials, the better their wear resistance.

The effect of processing on the tensile properties of metal materials:

The tensile performance of metal stamping parts can be affected differently by factors such as deformation sequence, processing speed, stamping performance, and processing temperature. Choosing a reasonable process according to the performance requirements can greatly improve the tensile performance of the work. Generally speaking, the higher the mold temperature, the more molecular kinetic energy, free volume of the melt, and activity of the chain segments inside the metal material will increase, thereby reducing the interaction between molecules and the viscosity of the melt, improving the transverse tensile strength of the metal material, and the processing time will be longer and tend to be flat. 2. There are often crystal defects such as dislocations inside metal materials, and the tensile properties of metal materials at room temperature mainly occur in the elastic and plastic deformation stages. The plastic deformation of metal materials mainly depends on the positional error method,