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我国易切钢的历史较短,50年代初期国内机械工业落后,基础差,根本不使用也不生产易切钢。1954年开始,由于汽车拖拉机、仪表仪器及军工等工业中,很多另件如接头管、紧固件、销、轴、螺钉螺帽等标准件,都要在自动机床进行加工生产,因而需要易切钢,才从国外引进硫易切钢A12、A20、A30、A40Mn等几个钢号,进行仿制生产。当时因汽车拖拉机及机电等产品,产量不大,故对易切钢的要求,矛盾不突出。60年代以后,国内机械工业的飞速发展,汽车拖拉机及机电产品日益增大,原引进易切钢的品种及其切削加工性能,都不能满足使用要求,而且易切钢产量也不够使用。因此,迫切要求扩大易切钢品种、增加产量和提高切削加工性能水平。
The history of China’s easy-cutting steel is relatively short. In the early 1950s, the domestic machinery industry lagged behind and the foundation was poor. It did not use or produce free-cutting steel at all. Since 1954, many standard parts such as fittings, fasteners, pins, shafts, screw and nuts, etc. have been processed in automatic machine tools in automobile tractors, instrumentation and military industries. Cutting steel, it was introduced from abroad Sulfur free cutting steel A12, A20, A30, A40Mn and several other steel, for imitation production. At that time, due to the automobile tractors and mechanical and electrical products, production is not large, so the requirements for easy cutting steel, the conflict is not prominent. Since the 1960s, the rapid development of the domestic machinery industry, the growing number of automobile tractors and mechanical and electrical products, the original introduction of easy-cutting steel varieties and cutting performance, can not meet the requirements, and not easy to cut steel production is not enough. Therefore, it is urgent to expand the varieties of free-cutting steel, increase the output and improve the cutting performance.