铌微合金钢中碳氮化铌化学组成的计算与分析

采用由热力学计算方法导出的二元微合金碳氮化物化学组成的理论计算公式,对一系列铌微合金钢中在奥氏体中沉淀析出的碳氮化铌的化学组成进行了实际计算,计算结果与有关文献给出的实验结果基本吻合。计算结果表明,碳氮化铌中碳化铌的摩尔分数x随温度的变化曲线一般为具有一极大值的连续上凸曲线;钢的化学成分中C量升高将使x增大,N量升高将使x减小,Nb量升高将使x增大;C、N量升高将使x取极大值的温度升高,而Nb量升高将使该极值温度降低。

CALCULATION FOR THE COMPOSITION OF NIOBIUM CARBONITRIDE IN NIOBIUM MICROALLOY STEELS

Using the thermodynatnical calculating method proposed before, the compositions of niobium carbonitride precipitated in austenite in a series of niobium steels have heen calculated, and the results are consistent with the experimental data reported. The calculated results have shown that the curve of the mole fraction x of niobium carbide in niobium carbonitride with temperature is a continuous curve with a maximum; the x value increases with increasing C and Nb contents and decreases with increasing N content in steel; the temperature at which the x is maximum increases with increasing C and N contents and decreases with increasing Nb content in steel.