Warp and weft intersection positioning method for weaving ceramic-based composite material

Abstract

The invention discloses a warp and weft intersection positioning method for weaving a ceramic-based composite material. Firstly, a direction gradient histogram is combined with a support vector machine to locate an area, containing warp and weft intersection positions, of a whole XCT slice; each positioned cross area can be positioned for multiple times at the same time, so that whether the crossareas are the same area or not is calculated according to the overlapping area ratio, inaccurate cross positions are removed and recognized according to the accuracy of each frame, and multiple sub-images containing warp and weft cross positions are output. Afterwards, lines of corresponding angles of warp and weft yarns in the sub-pictures are obtained through Hough transform, multiple vertexes of the warp and weft yarn intersection positions are obtained according to the straight line intersection principle, and four vertexes of a warp and weft yarn intersection area are extracted from the vertexes according to the characteristics of the intersection positions. The warp and weft intersection positioning method provided by the invention can further improve the identification accuracy of the warp and weft intersection, can be used for CMCs continuous XCT slices of plain weaving, 2.5 D weaving and other types, and is wide in application range and simple to operate.

Description

technical field [0001] The invention belongs to the field of mesostructure identification of woven ceramic matrix composite materials, and in particular relates to a method for locating intersections of warp and weft yarns of woven ceramic matrix composite materials. Background technique [0002] Ceramic matrix composites (CMCs, Ceramic Matrix Composites) are composed of continuous reinforced fiber bundles, interface and matrix. Compared with metal matrix composites, they have the characteristics of low density, better temperature resistance and corrosion resistance. Ideal candidate material for end pieces. Braided CMCs with complex preform structures have attracted extensive attention due to their excellent interlaminar shear resistance, impact resistance, and fracture toughness. [0003] X-ray computed tomography (XCT, X-ray computed tomography) is a non-destructive testing technology, which has the characteristics of not destroying the object but can clearly observe the ...

AI Technical Summary

Problems solved by technology

However, the current recognition of woven CMCs XCT slices is generally the whole slice input and the mesostructure classification, and there will be inaccurate recognition of the intersection of warp and weft yarns.

[0004] In summary, there is no report on the positioning method of the intersection position of warp and weft yarns in XCT slices of woven CMCs.

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