17CrNiMo6钢渗碳齿轮的盐浴分级淬火与油淬工艺

Martempering in molten nitrate and oil quenching processes of 17CrNiMo6 steel carburized gear

选用硝盐、快速淬火油作为淬火介质,分别对17CrNiMo6渗碳齿轮的三齿齿形试样进行了淬火+回火处理,分析了淬火介质冷却能力、模数、齿根下截面厚度对齿轮心部硬度、心部组织及对应含碳量的影响。结果表明,采用冷却能力较强的硝盐介质淬火时齿轮可以获得较高的心部硬度,心部板条马氏体形态尺寸更细,对应含碳量较低;在同种介质下淬火,随着齿轮模数、齿根下截面厚度的增大,心部硬度下降,模数较大的齿轮对应含碳量低,齿根下截面厚度较薄的齿轮心部板条马氏体更为明显。

The molten nitrate and rapid quenching oil were used as quenching media for quenching and tempering of three teeth tooth shape sample of 17CrNiMo6 steel carburized gear respectively. The influence of quenching medium cooling capacity,gear module and thickness in lower section of gear root on the core hardness and microstructure and relative carbon content was investigated. The results show that the higher core hardness,the finer lath martensite and the lower carbon content can be obtained when the gear is quenched by molten nitrate medium with stronger cooling capacity. The core hardness decreases with the increase of gear module and thickness in lower section of gear root,and large module gear corresponds to low carbon content,and lath martensite of thinner thickness in lower section of gear root is more apparent when the gear is quenched by the same medium.