Test Data Input to FE Material Model for SMC

Abstract

This thesis aims at correlating Carbon Fiber Sheet Moulding Compound (CF-SMC) composite material tests to a Finite Element (FE) material model. Six different geometrical objects, in total 28 samples, were cut out from two chassis components and they were all three dimensional (3D) scanned to obtain a representative computer aided design (CAD) model. Moreover, they were thermography scanned to detect possible defects or cracks within the material. Destructive testing was done on the samples and a Digital Image Correlation (DIC) setup was used to record the surface strain of the components. With the 3D scanned CAD model of the objects FE models were set up to represent the test. The models was made in detail to capture the test in whole. Multiple problems were found in the test setups which had to be adjusted in order to obtain data possible to compare. Large differences were experienced between the physical tests and FE models which indicated something was not captured correctly in the model or test. Validation tests were done on the machine, clamping systems and load application. Further, a test was done on a stainless steel bracket due to SMC’s complexity in material properties makes it difficult to model. Not all tests were performed in the timeframe of the thesis and 13 tests, four objects, were tested. A full correlation were not achieved due to the problems in the test setups. A conclusion is that something in the FE model or tests, is not behaving as expected and more eliminations is needed to eliminate errors to reach a good correlation.