A fiber placement device is described and methodology is given for proparing two dimensional and three dimensional combinatorial microcomposites. Although 2-D microcomposites with uniform fiber spacing have been prepared previously, the preparation of uniformly spaced 3-D microcomposites with (6 to 20) um diameter fibers is new. In addition, the concept of preparing test specimens that contain single fibers and multi-fibers arrays to admit the direct assessment of how fiber-fiber interactions influence fiber fracture and the "apparent" interfacial shear strength that is obtained from the fiber fragmentation test is also new. These experimental results contradict the prediction of type II shear-lag models that are most often used in composite failure models. Therefore, specimens of this type are needed to verify this trend. In addition, data from this new technology should delineate the factors that influence critical flaw nucleation in unidirectional laminate composites.
Citation: Experimental Mechanics
Pub Type: Journals
Failure analysis, Multi-Fiber array, Critical Flaw Nucleation