预应力混凝土用钢棒的热处理与组织性能研究

Study on Influences of Heat Treatment on Microstructure and Properties of Steel Bar for Prestressed Concrete

研究了淬火温度和回火温度对预应力混凝土用钢棒组织与力学性能的影响。结果表明,在相同回火温度下,抗拉强度均随着淬火温度的升高而先升高后降低,适宜的淬火温度为900℃;在相同淬火温度下,试样的抗拉强度都会随着回火温度的升高而逐渐降低;回火温度在370~460℃时的断后伸长率均满足≥5%的要求;结合标准对抗拉强度≥1 420 MPa的要求,预应力混凝土用钢棒适宜的回火温度为400℃。

The effect of quenching temperature and tempering temperature on the microstructure and mechanical properties of steel bars used in prestressed concrete is studied. The results show that when the tempering temperature is certain,tensile strength increases first and then decreases as the quenching temperature increases,and the suitable quenching temperature is900 ℃; when the quenching temperature is certain,the tensile strength decreases gradually with the increasing of the tempering temperature; the elongation at break of the steel bar tempered at 370 ~ 460 ℃ can satisfy the above 5% requirement,and combined with standard requirement that the tensile strength should be above 1 420 MPa,the suitable tempering temperature of steel bar for prestressed concrete is 400 ℃.