单轴反向加载对管线钢强度性能的影响规律研究

摘要

本文根据钢板在大直径管线钢管UOE成形工艺过程的变形情况,针对X70和X80管线钢材料进行了单轴反向加载试验,通过单向拉伸试验测试了在经历不同程度预压缩应变之后其屈服强度和抗拉强度的变化情况,并对其强度性能指标随预压缩应变的变化规律进行了分析与归纳.结果表明,在单轴反向加载条件下,两种材料的屈服强度均因包辛格效应而降低,其下降趋势均可拟合为二次函数;预压缩变形对试验材料的抗拉强度基本没有影响.%The uniaxial reverse loading tests of X70 and X80 pipeline steels are conducted based on the deformation of plate during UOE forming of large diameter LSAW line-pipe. Furthermore, the yield strength and the tensile strength are studied after uniaxial tension loading tests under different compressive pre-strain. The strength properties index influenced by the compressive pre-strain are analyzed and concluded. The results of the test show that the yield strength of both materials is decreased due to Bauschinger effect, the decreasing curve can be fit as a second order polynomial, and the compressive pre-deformation has not influence on tensile strength in general.