热膨胀法测45号钢的相变临界温度

Measuring the phase transition temperature of 45 steel by thermal expansion method

在加热过程中由于发生逆共析反应产生相变收缩效应,45号钢的线膨胀系数发生突变,由此得到相变临界温度.利用热膨胀法测量45号钢的线膨胀系数随温度的变化,升温速率为3~5℃/min,测得A C1点为737℃,A C3点为827℃,实验值与理论值吻合.

The linear expansion coefficient of 45 steel changed suddenly because of phase transition shrinkage effect caused by the reverse eutectoid reaction,thus the critical temperature was obtained.According to the thermal expansion method,the A C1 point of 45 steel was 737℃,the A C3 point was 827℃,the heading rate was 3~5℃/min,the experimental value was consistent with the theoretical one.