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近代粉末冶金技术由于便于控制合金成分、使金属材料组织细微而无偏析、高效率生产精密零件而无需切削加工或只需极少切削加工,因此在各种金属加工方法中发展最快。以日本为例,自七十年代中期以来,粉末冶金零件产量的增长速度比压铸件和普通锻件快2～3倍,在此期间,韧性铸铁件和灰口铸铁件的产量处于停滞中。但是,粉末冶金材料在由多孔制品向高强度制品的发展中,存在着如何使材料致密的问题。为此,国外自六十年代初研究粉末锻造技术。例如美国自1961年开始试制粉末锻造极靴、连杆等,但因粉末价格、材料淬透性以及模具寿命等技术问题而曾一度处于
Modern powder metallurgy technology in the development of a variety of metal processing method is the fastest growing due to easy control of the alloy composition, the microstructure of the metal without sub-segregation, high-precision production of precision parts without the need for machining or minimal cutting. Take Japan as an example. Since the mid-1970s, the output of powder metallurgy parts has grown 2 to 3 times faster than those of die-castings and normal forgings, and the output of ductile iron castings and gray cast irons has been stagnating during this period. However, powder metallurgy materials in the development of high-strength products from porous products, there is the problem of how to make the material densification. To this end, foreign countries since the early 1960s research powder forging technology. For example, the United States since 1971 for trial production of powder forging shoes, connecting rods, but because of powder prices, material hardenability and mold life and other technical problems once in