Test device for realizing expansion of various composite cracks and use method thereof

Abstract

The invention, which belongs to the technical field of mechanical test of materials, particularly relates to a test device for realizing expansion of various composite cracks and a use method thereof.The device comprises four fan-shaped arc plates, two U-shaped hooks, two perforated cushion blocks for adjusting the positions of samples, and a plurality of composite crack propagation samples. Three groups of through holes H1, i, H2, i and H3,i are formed in the fan-shaped arc plate, wherein the i is equal to 1,..., N, and N is the number of each group of through holes; the circle centers of each group of through holes are arranged on the same radius of the fan-shaped arc plate and are distributed at equal radian intervals, and the two through holes Hj, 1 and Hj,N at the two ends of each group of through holes are in 90-degree radian relation relative to the circle center of each fan-shaped arc plate, wherein the j is equal to 1, 2 and 3. Standardized I type, II type and III type composite crack propagation experiments and I / II type, I / III type and II / III type composite crack propagation experiments with different composite ratios can be realized, experimental results have certain comparability, and an experimental basis can be provided for researching the influence of different load composite ratios on composite crack propagation behaviors.

Description

technical field [0001] The invention belongs to the technical field of material mechanics testing and testing, and in particular relates to a testing device and a using method for realizing multiple composite crack extensions. Background technique [0002] In actual engineering structures, cracks are mostly in a composite deformation state. For example, in stiffened plates and shells in aerospace and ship structures, their cracks are often type I / II composite cracks with both opening and sliding types. Cracks in rotating components, such as generator shafts, are often type I / III compound cracks that open and torsion form. There are also ball bearings, railway wheels and gears that mainly suffer from type II / III composite cracks. [0003] Due to the complexity of complex fracture problems, complex fracture experiments have not been standardized so far. The AFM (all fracture modes) sample and its specific fixture designed by Richard and Kuna in 1990 were very complicated and...

AI Technical Summary

Problems solved by technology

However, different samples have different geometric structures, and at the same time, the corresponding loading devices produce different boundary conditions, which will inevitably lead to errors in experimental measurement

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