Three-dimensional Reconstruction Method Study of 2A12 Aluminum Alloy Fatigue Crack Based on Computed Tomography

doi:10.3901/JME.2015.24.063

Abstract

Abstract: The fatigue test about a 2A12 Al alloy bar with an annular notch under complex stress state gave the mechanism of the crack initiation and propagation of the material. And the result shows that the short crack only generated with the second-phase particle detachment from the matrix under complex stress condition when the fatigue cycle is sufficient. The crack slid along the slip band of the grains and presented as a zigzag path of crystallography crack. Industrial computed tomography technique is used to get more useful three dimensional information about the shape and size of the crack. Then the tomographic image is handled with image processing like contrast enhancement and outliers remove. From the perspective of image processing effect, outliers remove is a relatively ideal handling method for specimens with simple structure and continuous crack information. Adjustment of denoising radius could obtain more clearly crack sections. The processed image is reconstructed for three dimensional with the software of Matlab, and the 3D visualization of the crack agrees well with the real crack size.

Key words: 3D reconstruction；outliers remove, complex stress, computed tomography(CT), fatigue crack

WANG Lu, LI Pengzhi, WANG Zheng, WANG Rui. Three-dimensional Reconstruction Method Study of 2A12 Aluminum Alloy Fatigue Crack Based on Computed Tomography[J]. Journal of Mechanical Engineering, 2015, 51(24): 63-68.

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