Abstract: It is needed of refractory and anti-seismic rebar steel to maintain at 600 ℃ for more than 1 h,the high temperature yield strength can not be lower than the normal temperature yield strength of 2/3. In this paper, mechanical proper- tis of refractory and anti-seismic Cr-Mo-Nb steel at 20 ℃  and  600℃  are  studied. The results show that  the  developed 0.21%C,0.40%Si,1.25%Mn,0.32%Cr,0.40%Mo,0.015% Nb steel, at 20 ℃, the yield  strength is  400～520 MPa, strength-yield ratio is greater than1.25, at 600 ℃,the yield strength is 316 MPa, the ratio of high temperature yield strength to room temperature yield strength reaches 0.71,and the high temperature yield strength is 18 MPa higher than the 2/3 value of the standard requirement, which meets the requirements of refractory rebar steel.

Key words: Cr-Mo-Nb Refractory and Anti Seisnic Steel, Macro alloying 

摘要： 耐火抗震螺纹钢要求600 ℃≥1 h的高温屈服强度不能低于常温屈服强度的2/3。本文研究了Cr-Mo-Nb钢的耐火抗震螺纹钢的20 ℃和600 ℃力学性能。结果表明，开发的0.21%C，0.40%Si，1.25%Mn，0.32%Cr，0.40%Mo，0.015%Nb钢,在20 ℃室温时，屈服强度在400~520 MPa，强屈比大于1.25，在600 ℃高温时，屈服强度为316 MPa，高温屈服强度与室温屈服强度的比值达到0.71，并且高温屈服强度比标准要求2/3值高18 MPa，满足耐火抗震螺纹钢要求。