The effect of deep cold induced nano-carbides on the wear of case hardened components

Most studies of the wear improvements produced by the nano-carbides formed during deep cold treatment have been carried out on tool steels. In this study a carburising steel – 20MnCr5 – was carburised using typical industrial cycles, subjected to a range of cold treatments and its wear performance tested. It was found that under the conditions examined, converting any retained austenite to martensite increased wear. However, the nano-carbides formed by extended deep cold treatment at −196°C did significantly improve wear. Deeper cold treatment at −269°C did not produce any further improvement, even treatment for a much longer time.

大多数关于深冷处理过程中形成的纳米碳化物所带来的耐磨性提高的研究都是在工具钢上进行的。在这项研究中，一种渗碳钢——20MnCr5——采用典型的工业循环进行渗碳，经过一系列冷处理，并对其耐磨性能进行了测试。研究发现，在所考察的条件下，将任何残余奥氏体转变为马氏体会增加磨损。然而，在−196°C下进行长时间深冷处理所形成的纳米碳化物确实显著提高了耐磨性。在−269°C下进行更深程度的冷处理，即使处理时间更长，也没有带来任何进一步的改善。