论文部分内容阅读
一、前言铅系易切削钢具有优良的切削性能,含铅同时又含适量磷和硫的优质钢,其切削加工性能优良,有超级易切削钢之称。因此从1937年含铅钢研制出来以后,迅速发展成为主要的易切削钢系,并使易切削钢的品种和用途不断扩大,广泛地用来制造精密仪表、汽车和各种机械的重要零件。我国也早已开始生产含铅易切削钢,但品种、质量还不能满足需要,每年要从国外进口。为了满足工业发展的需要,节省外汇,很多特殊钢厂都试制了含铅钢。由于铅的一些特殊物化性能,使含铅钢不但在冶炼中有其特殊的困难问题和解决办法,同时也给含铅钢的检验上
I. Preface Lead-based free cutting steel with excellent cutting performance, containing lead and phosphorus at the same time and sulfur quality steel, its cutting performance is excellent, there are super easy cutting steel. Therefore, after the lead-based steel was developed in 1937, it rapidly developed into a major cutting steel line and expanded its variety and use of cutting steel. It is widely used to manufacture important parts of precision instruments, automobiles and various machines. China has already begun to produce lead-free cutting steel, but the variety and quality can not meet the needs of each year to be imported from abroad. In order to meet the needs of industrial development and save foreign exchange, many special mills have trial-produced lead-based steel. Because of the special physical and chemical properties of lead, lead-free steel not only has its own special difficulties and solutions in smelting, but also on the inspection of lead-containing steel