Modeling Intergranular Crack Propagation in Polycrystalline Materials
M.A. Arafin; and J.A. Szpunar;

Source CMC: Computers, Materials, & Continua, Vol. 14, No. 2, pp. 125-140, 2009
Download Full length paper in PDF format. Size = 463,511 bytes
Keywords Intergranular Cracking; Texture; Grain Boundary Character; Voronoi Algorithm; Markov Chain, Monte Carlo Simulations.
Abstract A novel microstructure, texture and grain boundary character based model has been proposed to simulate the intergranular crack propagation behavior in textured polycrystalline materials. The model utilizes the Voronoi algorithm and Monte Carlo simulations to construct the microstructure with desired grain shape factor, takes the texture description of the materials to assign the orientations of the grains, evaluates the grain boundary character based on the misorientation angle - axis calculated from the orientations of the neighboring grains, and takes into account the inclination of grain boundaries with respect to the external stress direction. Markov Chain theory has been applied to ensure the crack-path continuity and Monte Carlo simulation technique was employed to obtain the various possible orientation distribution of grains for any given texture description and to vary the spatial distributions of different grain orientations in the microstructure. Crack propagation behavior is simulated for both different types of fiber textures commonly found in Molybdenum polycrystals as well as the random polycrystals. The texture intensities and grain shapes were varied, for fiber and random textured samples, respectively, and resulting crack propagation lengths and percolation frequencies were compared.
PDF download PDF