NH_(3)-N_(2)-CO_(2)氮碳共渗气氛氮势的精确控制

Accurate Controlling of Nitrogen Potential in NH_(3)-N_(2)-CO_(2)

气体氮碳共渗气氛的氮势是非常重要的工艺参数。目前掺入N_(2)的NH_(3)-N_(2)-CO_(2)氮碳共渗工艺已得到了广泛应用,掺入氮气不仅能降低生产成本,还能提高气氛的氮势。通过计算CO_(2)与H_(2)反应而消耗的H_(2),推导出了精确计算NH_(3)-N_(2)-CO_(2)氮碳共渗气氛氮势的公式,并将其用于计算H13钢的NH_(3)-N_(2)-CO_(2)氮碳共渗气氛的氮势。计算和试验结果表明:H13钢采用NH_(3)-N_(2)-CO_(2)氮碳共渗获得无脉状氮化物渗层的临界氮势值为0.8。

Nitrocarburizing Atmosphere LI Dan Qingdao Fengdong Heat Treatment Co.,Ltd.,Qingdao 266108,Shandong China Nitrogen potential of gas nitrocarburizing atmosphere is a very important process parameter.At the present,NH_(3)-N_(2)-CO_(2)nitrocarburizing process into which nitrogen gas is introduced has been extensively used,and the introduction of nitrogen gas can not only reduce production cost but also increase nitrogen potential of the atmosphere.Through calculation of hydrogen consumption caused by reaction of carbon dioxide with hydrogen a formula used to accurately calculate nitrogen potential of NH_(3)-N_(2)-CO_(2)nitrocarburizing atmosphere was derived,and applied to calculation of nitrogen potential of NH_(3)-N_(2)-CO_(2)atmosphere in which H13 steel was nitrocarburized.The calculated and experimental results showed that the critical nitrogen potential value of NH_(3)-N_(2)-CO_(2)atmosphere in which H13 steel is nitrocarburized and develop the case without vein nitride was 0.8.