Abstract: The materials basic characteristics of structure, austenite grain coarsening and phase transformation point of RL40 steel for flexpline (/% ：0.40C, 0.90Cr, l. 85Ni, 0.25Mo, 0.05Nb, 0.016Ti) has been studied by the quantitative analysis of optical microscopy and thermal expansion experiment. The results show that the microstructure of the rolled bar is bainite + martensite, the average grain size of primary austenite is 14. 0 μm, and the austenite grain size rating is 9. 0 ~ 9. 5, and the average standard deviation is 0. 46 ~ 0. 048. The transformation point Ac₁ is 729 ℃, Ac₃ is 769 ℃, Ms is 28 ℃, and the austenite grain coarsening temperature is 1 000 ℃.

摘要： 通过光学显微定量分析和热膨胀实验,研究了柔轮用钢RL40（/%:0.40C,0.90Cr,1.85Ni,0.25Mo,0.05Nb,0.016Ti）的微观组织、相变点和奥氏体晶粒粗化规律等材料基本特性。结果表明:轧材组织为贝氏体+马氏体,原始奥氏体晶粒平均尺寸为14.0 μm,晶粒度级别为9.09.5,平均标准偏差均在0.46~0.48;相变点Ac₁为729℃,Ac₃为769 ℃,Ms点为281 ℃;奥氏体晶粒粗化温度为1 000℃。

关键词: 谐波减速器柔轮用钢RL40, 粗化温度, 相变点;