ANALYTICAL AND EXPERIMENTAL APPROACH TO DAMAGE AND RESIDUAL STRENGTH OF FIBERGLASS COMPOSITE AUTOMOTIVE FRAME RAILS DURING MANUFACTURING

The use of composite materials in the construction of various structur al components of the car body has gained an increasing interest in the automotive industry. In relation to this, the crashworthy ability of an automotive frame rail of hour glass cross-section, made of a glass fiber/vinylester composite and designed for use in the apron construct ion of the car, when subjected to axial collapse and bending, has been extensively investigated in this paper. An important problem arose, d ealing with the delamination observed at the corners and curved parts of the hourglass section which may be attributed to the manufacturing processing, resulting in severe limitations in the load-carrying capac ity of this structural component. The effect of the residual stress an d strain fields induced during fabrication was examined both theoretic ally and experimentally and possible failure mechanisms observed were investigated and discussed.