Metal plastic forming is a process in which the plastic properties of metal materials are used to make them have the required shape. After forming, the structure and properties of metal materials are improved. In general, the components which are subjected to alternating load or poor stress conditions can meet the use requirements only through the plastic forming process. Plastic forming is a chip free forming method, which can make the workpiece obtain good streamline shape and reasonable material utilization. With the plastic forming method, the size of the workpiece can reach a high precision and have a high production efficiency.

Plastic forming includes cold forming, warm forming and hot forming. The influence of temperature on the properties of materials should be considered in warm forming, and the creep effect of materials should be considered in hot forming. Metal plastic forming includes block forming, sheet forming and rolling (see plastic mechanics). All kinds of plastic forming are based on the premise that metal materials have plastic properties, all need external force, all have the influence of external friction, and all follow the common laws of metal science and plastic mechanics.

The method of applying the principle of plastic mechanics to study the law of metal forming is called plastic analysis of metal forming. Its task is: ① to study various solutions of mechanics in the process of plastic forming, to analyze the distribution law of stress and strain in the body of deformation, and to determine the deformation force and deformation work, so as to reasonably select the tonnage of equipment and the strength of die. Secondly, the change law of the strain and size of the component in the process of plastic forming is studied, and the appropriate blank and the reasonable shape of the intermediate blank are selected to achieve the desired shape of the component optimally. Thirdly, the influence of processing conditions such as temperature and strain rate effect on the plastic processing resistance of metal and the measures to improve the toughness of metal and reduce the resistance are studied in order to obtain components with good performance. The plastic analysis methods of metal forming mainly include principal stress method, slip line method, upper limit method and finite element method, while the common experimental methods are apparent plasticity method and dense grid moire method.