易切削系非调质塑料模具钢的加工性

Mackinability of Free-Cuting Unquenched Plastic Die Steel

研究了易切削系非调质型塑料模具钢的加工性能，通过诸项切削加工性对比实验证实，该塑料模具钢的可切削加工性能优于４５钢调质，并通过磨削、抛光性能实验证明该钢具有良好的磨、抛性能，分析了Ｓ系、Ｓ－ＲＥ系以及Ｓ－Ｃａ－ＲＥ系钢的易切削相，探讨了易切削机理，这主要是易切型夹杂物在切削中起应力集中源、包裹和润滑作用。

The machinability of the free-cutting unquenched plastic die steels was studied. Compared with the commercial 0.45Wt% carbon steel as-queue bed /tempered, the steels we re proved to besuperior to the latter in machinability including chipbreakability, cutting force, tool life, machined surface, etc. The steels were proved of fine grind-polishability by grinding and polishing experiments too.The free-cutting phases in the S steel, S-RE steel and S-Ca-RE steel were analysed.It was discussedthat the free-cutting mechanism is mainly because of its inclusions which play important role in stressconcentration, lubrication and encasing.