摘要
Material forming process of manufacturing the parts by directly acting on the materials is the most fundamental content of the advanced manufacturing technology (AMT) and the general summation of physical process of production[1].
Material forming process of manufacturing the parts by directly acting on thematerials is the most fundamental content of the advanced manufacturing technology (AMT) and thegeneral summation of physical process of production[1]. The advancement and development of formingprocess radically represent the level of manufacturing theory and technology of a country and/or aregion. Precision cold extrusion is an important process of material advanced forming technology. Inthe past 30-40 years, big development has been achieved in this area and an apprehensive theory andpractical knowledge system has been formed. For example, deformation theory and typical forms offorward extrusion, backward extrusion and combined extrusion in cold extrusion are developed; manyparts produced by cold extrusion and its constructional system of technological knowledge areintroduced and summarized[5 8]. The International Cold Forging Group (ICFG) and the organizations ofcold forging technology at the each member country have also helped researchers and technologiststo develop new technologies and theories by providing financial support and organizing technicalconferences and workshops. Consequently, cold extrusion and cold forging have become an importantfield parallel to latest immerging areas such as 'near net shape forming', 'accuracy forming greenmanufacturing' and so on.