Nitrocarburizing was carried on to 45 # steel specimens in the RJJ —105 pit type gas nitriding furnace, the nitrocarburizing agents were ammonia and methanol. Combined with the working principle of soft nitriding, the major process parameters such as the supply of ammonia and methanol and nitrocarburizing time were controlled to obtain different thickness on surface compound layer, which is the white light layer. The results showed that when nitrogen potential reached a certain amount at 570℃, the white layer was becoming more and more thickening and the subsurface micro-hardness was enhanced with the extension of nitrocarburizing time, but nitrocarburizing time was aver for four hours or more. The white layer thickness had no obvious change, but the obvious ralio of porosity layer appeared on surface compound layer and the subsurface microhardness was decreasing with the extension of time.%在RJJ - 105井式气体渗氮炉中,对45钢试块进行氮碳共渗,渗剂为氨气和甲醇.结合软氮化的工作原理,通过控制氨气供量、甲醇滴入量和氮碳共渗时间等主要工艺参数,使试块获得不同厚度的表层化合物层,即白亮层.结果表明,在570℃下,当氮势达到一定量以后,随着氮碳共渗时间的延长,白亮层增厚,表层显微硬度增加,但氮碳共渗时间超过4h以上时,随着时间的延长,白亮层厚度无明显变化,但是表面出现明显的疏松,表层显微硬度下降.
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