含硼微合金钢中硼氮化物形成的热力学分析

应用合金元素在奥氏体中的固溶度积公式,对含硼铝镇静钢,Ti-B和Ti-Nb-V-B系微合金钢中各种析出相的析出关系和析出量及其对奥氏体中固溶硼质量分数的影响进行了热力学分析.结果表明:含硼铝镇静钢中BN的析出优先于Al N的析出,使增加奥氏体稳定性的B的有效质量分数减少;提高含硼钢中的固溶B质量分数的有效方法是加入比B与N的结合力强的Ti;复合微合金钢中Nb,V的质量分数对固溶B的质量分数几乎没有影响,只与钢中加入Ti的质量分数有关,Ti-B和Ti-Nb-V-B系微合金钢中Ti的质量分数最少为钢中N质量分数的3.4~3.8倍.

Thermodynamic Analysis of Boron Nitride Formation in Boron Microalloyed Steel

In aluminum killed boron steel， Ti-B steel and Nb-V-B microalloyed steel， the precipitation relation and the precipitate content of the various precipitates， and the influence of those on the solid solution boron content were thermodynamically analyzed by using the solid solubility formula of alloy elements in austenite. The results showed that the precipitation of BN is prior to the precipitation of AlN， so the effective boron content to increase the stability of austenite decreases in the aluminum killed boron steel. The addition of Ti is an effective method of increasing the solute boron content in the boron steel， because the bonding force between Ti and N is stronger than that between B and N. The contents of Nb and V have little influence on the solute B content in microalloyed steel， but the solute boron content only is related to Ti content added in the steel， and Ti content is 3.4~3.8 times of N content in the Ti-Nb-V-B microalloyed steel at least.