球化退火中Nb对GCr15钢碳化物析出和球化的影响

Effect of niobium on carbide precipitation and spheroidization during spheroidizing process in steel GCr15

通过球化退火实验,采用定量金相分析和显微硬度测定,研究了球化退火过程中微合金Nb对轴承钢GCr15碳化物析出和球化的影响。结果表明:实验钢800℃加热1 h后以15℃/h冷却球化退火过程中,添加0.018%和0.040%Nb虽然没有影响GCr15钢的碳化物析出和球化的温度,均为720~740℃,但是显著加快了GCr15钢碳化物析出和球化的速率。

Effect of niobium microalloying on carbide precipitation and spheroidization during spheroidizing process in bearing steel GCr15 was investigated by spheroidizing treatment,quantitative metallographic analysis and microhardness test. The results show that there is no effect of 0. 018% and 0. 040% niobium addition on temperature range of carbide precipitation and spheroidization of the steel,which is all720-740 ℃,during heating to 800 ℃ for 1 h then cooling by 15 ℃ / h spheroidizing process. However,the rate of carbide precipitation and spheroidization in the temperature range observably increases by the niobium addition in the tested steel.