中文摘要：

为了得到高温下耐火钢的材料特性，对马钢集团开发的耐火钢在高温下的力学性能进行了试验研究。通过高温下的恒温加载拉伸试验，得到不同温度下耐火钢的屈服强度、极限强度、延伸率、面缩率和应力一应变关系，并测定高温下耐火钢的热膨胀系数，采用悬丝耦合共振法测定高温下耐火钢的初始弹性模量。试验表明，马钢耐火钢在600℃时的屈服强度大于常温下的2／3，弹性模量大于常温下的3／4。通过对试验结果的分析，拟合得到耐火钢的各力学指标参数随温度变化的计算公式，这些公式可用于耐火钢结构抗火性能的分析与设计。

英文摘要：

Experiments are carried out to determine the high-temperature mechanical properties, such as yield strength, tensile strength, elongation, Poisson ratio and stress-strain relationship, of fire-resistant steel made by the Maanshan Iron ＆ Steel Co. Ltd.. A coupled vibration method on suspended free poles is employed to determine the initial Young＇s modulus at elevated temperatures, also the thermal expansion coefficients of fire-resistant steel. Test results indicate that the yield strength of fire-resistant steel at 600℃ is higher than the yield strength at ambient temperature by two thirds, and the initial Young＇s Modulus at 600℃ is higher than of that at ambient temperature by three quarters. In conclusion, the functions of coefficients for mechanical properties of fire-resistant steel under variable temperatures are developed by using a regression analysis.