三次奥氏体化可以使碳化物尺寸得到细化，并且随着奥氏体化温度的提高，碳化物尺寸越细小，但是三次奥氏体化并不能使韧性、硬度和抗弯性能提升，反而会降低硬度、韧性和抗弯强度；二次奥氏体化可以提高钢的韧性和抗弯强度，并且性能与第一次奥氏体化温度密切相关，随着首道次奥氏体化温度的提高，钢的性能有所恶化，首道次最佳奥氏体化温度为1050℃。

The third austenitizing can refine the size of carbides, and with the increase of austenitizing temperature, the size of carbides will become smaller. However, the third austenitizing can not improve the toughness, hardness and bending strength, but will reduce the hardness, toughness and bending strength; The second austenitizing can improve the toughness and bending strength of steel, and the performance is closely related to the first austenitizing temperature. With the increase of the first austenitizing temperature, the performance of steel deteriorates. The first optimum austenitizing temperature is 1050 ℃.