【摘要】 采用基于有限元反射模型的SFS(shapefromshading)算法对锆-4合金低周疲劳断口进行三维重建,定量描述了断口表面的三维形貌。然后,根据小岛法的基本理论,研究了断口三维形貌的分维计算方法,计算了一系列平行于断口表面的分维值。结果表明:在40%～60%高度范围内,根据小岛法作出周长L(η)-面积A(η)在双对数图上呈近似直线关系,表明Zr-4合金断口具有良好的分形特征;分形维数D变化范围为1.5809～1.6450,平均值1.6031,标准差0.0237。表明在此切割高度范围内,高度对分维值影响较小。更多还原

【Abstract】 A new approach of calculating SFS (shape from shading) based on finite-element reflection model had been established and applied to reconstruct the 3D morphology of Zircaloy-4 fatigued fracture. The 3D detail figure of metal faultage was investigated in terms of the basic theory of Small Island Method. A series of fractal dimension values of parallel to the surface of faultage was attained. The results show that, as the height change in the rang of 40% to 60%, the perimeter L(η) and the area A(η) is closed to be a line in double logarithmic coordinate axes. Likewise, the result testifies that the faultage of Zircaloy-4 has excellent characteristic. As the value of fractal dimension only fluctuate in the narrow rang of 1.5809 to 1.6150 with statistical mean of 1.6031 and standard deviation of 0.0237, it’s reasonable that the height given has slight influence on the fractal dimension.更多还原