USE OF THE WYOMING COMBINED LOADING COMPRESSION (CLC) FIXTURE TO TEST UNIDIRECTIONAL COMPOSITES

摘要

The Wyoming Combined Loading Compression (CLC) test fixture was originally developed to determine the compressive properties of cross-ply and other composite laminates. Unidirectional lamina properties can be derived from cross-ply test data by utilizing a back-out factor. However, direct compression testing of unidirectional composite is sometimes necessary. A study was conducted to compare CLC-produced unidirectional composite data with backed-out cross-ply failure strength and modulus data.Three different specimen geometries, fabricated using a unidirectional AS4/3501-6 carbon/epoxy composite, were tested using the CLC fixture. Two of the specimen geometries were straight-sided with bonded tabs, similar to the specimen configuration specified in ASTM D3410. The third specimen geometry was also straight sided, but was tapered through-the-thickness to reduce the cross-sectional area in the gage section of the specimen. Resulting compression test data from the three specimen configurations were compared with previously obtained CLC results for a cross-ply AS4/3501-6 composite. The tapered geometry produced results very similar to that of the cross-ply.