长屈服平台钢应力─全应变曲线的两段ROR关系直接拟合法

Two-section Piecewise Fitting Method for the Ramberg-Osgood Relationship of Stress-full Strain Curve for Steel with Long Yield Plateau

本文发展了一种新的R－O关系二段直接拟合应力一全应变曲线的方法（以平台终点为分段点）。计算证明，这种新的两段拟合方法所得到的EPRI工程方法J积分值与用有限元方法分析所得到的J积分值相比是精确的。

Some steels. such as 16MnR. have long yield plateau and do not meet the RambergOsgood Relationship. They are not adapted to calculation of J-integral using EPRI methed. In this paper. a new method, the two-section piecewise fitting method, is proposed. Calculation has proved that it is accurate in J-integral using finite element analysis.