回火温度对建筑用耐火钢组织和力学性能的影响

Effects of Tempering Temperature on Microstructure and Mechanical Property of Refractory Steel

研究了回火温度对耐火钢组织和性能的影响。结果表明,回火温度低于500℃时,耐火钢的晶粒尺寸变化不大,当回火温度高于500℃以后,耐火钢中晶粒尺寸开始快速增大。当回火温度达到700℃时,耐火钢中的晶粒粗大明显,尺寸达到7.13μm。随回火温度的升高,铁素体的面积分数变化不大,始终维持在85%左右;M-A的面积分数则不断减小。回火处理可以明显改善耐火钢的高温强度,使其在高温下屈服强度不降低太多。

The effects of tempering temperature on microstructure and mechanical property of refractory steel were studied.The results show that when the tempering temperature is lower than 500 ℃,the grain sizes of the refractory steel change little; but when the tempering temperature is higher than 500 ℃,the grain sizes of the refractory steel increase drastically.When the tempering temperature achieves 700 ℃,the grain sizes of the refractory steel reach 7.13 μm.The area fraction of ferrite is about 85% with tempering temperature increasing,but the M-A area fraction decreases gradually.The high temperature strength of the refractory steel can be improved by tempering,thus the yield strength won’t decrease too much at high temperature.