固体硼-铬-稀土共渗研究

固体法渗硼不存在气体法和液体法的缺点,发展迅速[1,2]。但是,限制固体渗硼应用的最大障碍是渗硼层浅、脆性高。研究证实,ＲＥ元素作为催渗剂可明显提高渗硼速度,然而改善渗硼层脆性的作用有限[3～5]。选择电负性比铁低的过渡族元素与硼共渗可获得单一(Ｆｅ,Ｍｅ)2Ｂ相、利于降低渗硼层脆性[6]。因此,为克服固体渗硼的弱点,采用以渗硼为主的硼—铬—稀土共渗不失为一种新的尝试。作者对硼—铬—稀土共渗进行了较多的研究[7～9]。本文在上述工作的基础上,对共渗机理进行初步的研究分析。1　试验材料及方法试验材料采用45钢,试样尺寸为14ｍ…

Study on Pack RE-chrome-boronizing

The mechanism of pack RE|chrome|boronizing and the effects of RE and Cr elements on the formation of RE|chrome|boroinized layer were studied by the aid of thermodynamic calculations and the layers compositions analyses in this paper.The results show that boronizing plays a leading role in pack ER|chrome|boronizing because active RE and Cr atoms are obtained by reducing the solid materials,and then RE and Cr atoms dissolve in the RE|chrome|boronized layer,be fine and close (Fe,Cr,RE)-2B phase in texture,by way of passing the grain boundary chiefly and replacement|spreading separately.The spreading of RE and Cr atoms plays an important role in forming the fine columnar grains and decreasing surface|layer voids of RE|chrome boronized layer.