高温后冷轧带肋钢筋力学性能的试验研究

Study on Mechanical Property in Properties of Cold-Rolled Deformed Bar After Undergoing High-Temperature

为了得到高温后冷轧带肋钢筋的材料特性,对该钢筋(CRB550)在高温后的力学性能进行了试验研究。通过高温后的加载拉伸试验,得到了不同温度下冷轧带肋钢筋的屈服强度、极限强度、伸长率、面缩率和应力应变曲线,并测定高温后冷轧带肋钢筋的弹性模量和热膨胀系数。试验表明:冷轧带肋钢筋在400℃以内极限强度有小幅回升。随后随着经历温度的升高极限强度逐渐下降。通过对试验结果的分析,拟合得到冷轧带肋钢筋高温后的力学性能随经历温度变化的回归数学模型公式。

Experiments were carried out to determine the mechanical properties after undergoing high-temperature,such as yield strength,tensile strength,elongation,poisson ratio and stress-strain relationship,of the cold-rolled deformed bar（CRB550）.The initial Young＇s modulus and also the thermal expansion coefficient of the cold-rolled deformed bar were determined.Test results indicate that the ultimate strength of the cold-rolled deformed bar under 400℃ increases with increasing temperature,and the ultimate strength of the cold-rolled deformed bar decreases with increasing temperature over 400℃.In conclusion the functions of coefficients for mechanical properties of cold-rolled deformed bar under variable temperatures are developed by using a regression analysis.