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通过在渗扩介质与被渗样品间施加合适参数的直流电场予以实现快速粉末渗铬。选择碳素钢(45钢和20钢)为研究对象,分析了直流电场对渗铬层显微组织、渗层厚度及温度场的影响,分析了施加直流电场条件下温度对渗层厚度的影响,并研究了施加直流电场快速渗铬获得的渗层的高温抗氧化性。结果表明,直流电场可降低粉末渗铬温度,显著增加渗速;可将常规粉末渗铬温度950～1100℃降低到850℃以下;加热温度为700～850℃时,通过施加合适的直流电场,渗铬层厚度可达到60μm以上。直流电场不仅对试样有加热作用,而且在两极间形成温度差。快速渗铬新工艺获得的渗铬试样在700℃以下具有良好的抗氧化性能。
Rapid powder chromizing is achieved by applying a suitable DC electric field between the infiltration medium and the infiltrated sample. The effects of DC electric field on the microstructure, thickness and temperature field of chromized layer were analyzed, and the influence of temperature on the thickness of the layer was analyzed under direct current (DC) electric field. , And studied the high temperature oxidation resistance of the infiltrated layer obtained by direct chromizing with direct current electric field. The results show that the DC electric field can reduce the powder chromizing temperature and significantly increase the infiltration rate. The conventional powder can reduce the chromizing temperature from 950 to 1100 ℃ to below 850 ℃. When the heating temperature is from 700 to 850 ℃, Chromizing layer thickness can reach more than 60μm. DC field not only has a heating effect on the sample, but also the temperature difference between the two poles. The chromizing samples obtained by the new rapid chromizing process have good oxidation resistance under 700 ℃.