齿圈渗碳淬火过程的碳浓度场和组织场数值分析

The Analysis of Carbon Concentration Field and Structure Field Value for Gear Ring Carburizing and Quenching Process

根据齿圈的热处理工艺,基于渗碳过程的有限元数学模型,对齿圈的变碳势渗碳过程进行了数值模拟。模拟结果表明,在强渗期表面碳浓度升高较快,在扩散期则缓慢降到炉气碳势值,最终具有理想的S形曲线分布。在渗碳过程模拟结果的基础上,对淬火过程的组织分布也进行了数值模拟。结果表明,马氏体转变量与碳含量成反比。工件实际检验结果也验证了这一结论。

According to the heat treatment process of gear ring, as well as on account of the finite element mathematical model for carburizing process, the carbon potential numerical simulation of carburizing process for gear ring has been performed. Its simulation results indicates that the surface carbon concentration increases quickly during the deep carburizing period, and then during the diffusion period it slowly decreases to the carbon potential value of furnace gas, finally it distributes as the perfect S-shaped curve. On the basis of simulation results for carburizing process, the structure distribution numerical simulation of quenching process also has been performed. Its results indicates that the martensite transformation content is inversely proportional to the carbon content. Furthermore, this conclusion has been proved by the workpiece actual test results.