卷取温度对X80管线钢组织和性能的影响

Influence of Coiling Temperature on Microstructure and Properties of X80 Pipeline Steel

在实验室450 mm轧机上用控制轧制和控制冷却的方法制备了X80管线钢板,采用光学显微镜、透射电镜和力学性能试验机等研究了卷取温度对该钢显微组织和力学性能的影响。结果表明:当卷取温度在463～597℃范围内变化时,随着卷取温度的升高,该钢组织中针状铁素体含量增加,M-A岛更细小均匀,显微组织明显细化;在597℃卷取时,该钢的屈服强度达到650 MPa,抗拉强度达到790 MPa,伸长率达到30%左右。

X80 pipeline steel plate was prepared by controlled rolling and controlled cooling method using Ф 450 mm laboratory rolling mill. The influence of coiling temperature on the microstrueture and mechanical properties of the steel was investigated by means of optical microscope, TEM and mechanical property tester. The results show that when the coiling temperature increased from 463 ℃ to 597 ℃, the content of acicular fertile （AF） in X80 pipeline steel increased, and the M-A island became finer and well-proportioned. When the coiling temperature was 597 ℃, the yield strength and tensile strength of X80 pipeline steel could be 650 MPa and 790 MPa respectively, and the elongation was about 30%.