40Cr 钢 的 高 温 蠕 变 行 为

研究了40Cr钢在不同温度和应力水平下的蠕变行为，并根据实验数据绘制得到蠕变曲线.在实验条件下，40Cr钢的蠕变曲线呈现出较长的稳态阶段和较短的减速阶段与加速阶段.并且其蠕变的稳态速率可以用Norton Power规律来描述，蠕变数据符合Monkman Grant关系的一般形式.同时，基于实验数据，建立了40Cr钢高温蠕变的非线性本构方程，并通过最小二乘法确定本构方程中的参数.将该本构方程计算得到的结果与实验数据进行了比较，发现用该本构方程可以较好地描述40Cr钢的蠕变行为.

The Constitutive Relationship of Elevated Temperature Creep of 40Cr Steel

The creep behaviors of 40Cr steel were investigated at various temperatures and stresses.And the creep curves based on the experimental datas were plotted.It can be observed that the steady creep and the accelerating creep processes are the dominant parts of the creep curves of the 40Cr steel in the experimental conditions.Besides,the steady creep rates can be described by the Norton-Power law and the creep data can be fitted by the Monkman-Grant relationship.Then,a nonlinear constitutive equation for the 40Cr steel was proposed according to the experimental data.The parameters of the equation were determined by the least square method.At last,it can be found that the proposed equation can describe the creep behaviors of the 40Cr steel quite well by comparing the theoretical results calculated by the proposed equation and the experimental data.