渗碳齿轮内氧化控制技术研究

摘要

In order to relief the phenomenon that gear is easy to produce deep internal oxidation in the carburizing process ,we adjus-ted the carbon potential to control the internal oxidation ,and discussed the internal oxidation technology about 18CrNiMo7-6 carbu-rized gear .In actual production process ,by changing the carbon potential at diffusion zone of three groups of carburized specimens , the carburizing trend of specimens in the furnace was controlled ,the microstructures of samples were analyzed ,and the depths of in-ternal oxidation layers of samples were compared .The test results show the carbon potential increases from 0 .7% C to 0 .8% C ,and the depth of internal oxidation will decrease from 22μm to 15μm .Thus the carbon potential is one of the important factors which in-fluence the oxidation depth .It is appropriate to increase the carbon potential at diffusion zone to reduce the internal oxidation .%针对齿轮在渗碳过程中容易产生较深的内氧化这一现象，提出通过调节碳势的手段抑制内氧化的产生，探讨了18CrNiMo7-6材料的渗碳齿轮内氧化控制技术。采用控制变量法改变扩散区的碳势，调节试样在渗碳过程中碳势的变化，分析试样的金相显微组织，比较内氧化层深度。试验结果表明：扩散期碳势从0.7％ C上升到0.8％ C时，内氧化深度从22μm下降到15μm。由此可见碳势是影响内氧化深度的一个重要因素，可适当提高扩散期碳势，抑制内氧化产生。随着碳势的增加，硬化层层深有所提高，碳化物也随之增加。