我厂生产的材料试验机中,有一种主要零件活塞,是用42CrMo材料制成的,长1056mm,最大直径为361mm,件重330kg。外形如图1所示。该件在LD-50型离子氮化炉中进行氮化,由于批量太少,只能单件装炉。所遇到的问题是辉光很不均匀,从阴极盘往上,越来越淡薄,最后消失,更谈不上温度的均匀了。为了解决这个问题,我们做了一个如图2所示的 I plant material testing machine, there is a main part of the piston is made of 42CrMo material, length 1056mm, maximum diameter of 361mm, piece weight 330kg. Figure 1 shows the appearance. The piece of nitriding in the LD-50 type ion nitriding furnace, due to the volume is too small, only a single furnace. The problem encountered is glow is very uneven, from the cathode disk up, more and more light, eventually disappear, let alone the temperature of the uniform. In order to solve this problem, we made one as shown in Figure 2