汽车车轮用低碳Nb微合金钢中的析出行为研究

Precipitation in low carbon steel microalloyed with Nb for automotive wheel

通过热模拟试验,研究了Nb微合金钢中的碳氮化析出物在高温及低温等温过程中的析出行为。试验结果表明:在高温时,应变诱导NbC析出需要一定的孕育时间。随着高温等温温度的升高,析出物的数量增多。当高温等温时间达到300s时,单一析出转变为复合析出,同时随着温度的升高,复合析出聚合长大,数量明显减少,形状变为不规则形状;在低温时,随着等温温度的升高,析出数量略有增多。随着等温时间的延长,析出物的数量略有增多,尺寸略有增大。

Carbonitride precipitation behavior of Nb microalloyed steel during holding at high temperature and low temperature was studied through thermal simulation. The results show that in high temperature region incubation period is necessary for strain induced NbC precipitation, and increasing the holding temperature leads to an increase of precipitatioru Simple precipitation changes to complex precipitation when holding for 300 s at high temperature. Meanwhile, complex precipitation converges and grows, the amount of precipitation decreases and the shape of precipitation changes with the increasing of holding temperature. In low temperature region, the amount of precipitation goes higher appreciably with holding temperature and time. The size of precipitation increases little with increasing holding time.