Wang Yanhui, Zhang Fucheng, Yang Zhinan, Lv Bo, Zheng Chunlei
State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China.
National Engineering Research Center for Equipment and Technology of Cold Strip Rolling, Yanshan University, Qinhuangdao 066004, China.
Materials (Basel). 2016 Nov 25;9(12):960. doi: 10.3390/ma9120960.
In the present work, the nanostructured bainitic microstructures were obtained at the surfaces of a carburized steel and a high-C steel. The rolling contact fatigue (RCF) performances of the two alloy steels with the same volume fraction of undissolved carbide were studied under lubrication. Results show that the RCF life of the carburized nanostructured bainitic steel is superior to that of the high-C nanostructured bainitic steel in spite of the chemical composition, phase constituent, plate thickness of bainitic ferrite, hardness, and residual compressive stress value of the contact surfaces of the two steels under roughly similar conditions. The excellent RCF performance of the carburized nanostructured bainitic steel is mainly attributed to the following reasons: finer carbide dispersion distribution in the top surface, the higher residual compressive stress values in the carburized layer, the deeper residual compressive stress layer, the higher work hardening ability, the larger amount of retained austenite transforming into martensite at the surface and the more stable untransformed retained austenite left in the top surface of the steel.
在本研究中，在渗碳钢和高碳钢表面获得了纳米结构贝氏体组织。研究了两种具有相同体积分数未溶碳化物的合金钢在润滑条件下的滚动接触疲劳（RCF）性能。结果表明，尽管两种钢在大致相似的条件下，其化学成分、相组成、贝氏体铁素体板条厚度、硬度以及接触表面的残余压应力值等方面存在差异，但渗碳纳米结构贝氏体钢的RCF寿命优于高碳纳米结构贝氏体钢。渗碳纳米结构贝氏体钢优异的RCF性能主要归因于以下原因：顶面碳化物弥散分布更细、渗碳层中残余压应力值更高、残余压应力层更深、加工硬化能力更强、表面有更多的残余奥氏体转变为马氏体以及钢顶面剩余的未转变残余奥氏体更稳定。
