基于变形历史的管线钢屈服强度预测模型研究

Yield stress prediction model based on the deformation history of pipeline

在管线钢管成形过程中,因为正反两个方向塑性变形发生不同程度的变化,使管体和毛坯板之间的屈服强度产生差异。以国内某厂生产的X90钢板为研究对象,采用正向预拉伸—卸载—反向压缩的试验方法,分析了在不同程度的预变形条件下,材料的反向屈服强度的变化规律。结果显示,随着预应变的增加,板料反向屈服强度呈现先降低后升高的趋势,预应变为5.455%时,反向屈服强度取得最小值。基于Hodge强化理论建立了这种材料的反向屈服强度预测模型,并通过ABAQUS二次开发,实现了X90管线钢单次反向加载条件下的屈服强度预测。验证结果表明:模型预测结果与实验结果吻合较好,相对误差未超过2%。

Due to the different degrees of plastic deformation in forward and reverse directions during the pipeline forming process,the yield strength between the line pipe body and the blank plate is different. Taking X90 steel produced in a domestic factory as a research object,adopting the method of pre-stretching in forward direction-unloading-reverse compressing,the reverse yield strength variation rules of the material under different degrees of pre-deformation were analyzed. The results show that with the increase of pre-strain,the reverse yield strength shows the trend of decreasing at first and then increasing subsequently. When the pre-strain reaches to 5. 455%,the reverse yield strength has the minimum. The reverse yield strength prediction model of this material was established based on the Hodge theory,and the reverse yield strength prediction of X90 steel under single reverse loading condition was achieved via the ABAQUS secondary development platform. The verification results show that the predicted result agrees well with the experimental result and the relative error is less than 2%.