BS in Materials Engineering
Materials Engineering Department
Callaway Golf receives a proprietary blend of prepreg material from Quantum Composites. Callaway processes the prepreg in-house and supplied 254mm x 254mm x 1.3mm panels of carbon fiber sheet molding compound (CFSMC) for characterizing. Tensile strength was analyzed by conducting tensile tests per ASTM D3039. Tensile coupons were cut to 254mm long by 25.4mm wide. Tabs were constructed from 1.6mm thick GFRP printed circuit board material. A commercial grade two part epoxy was used to bond the tabs to the CFSMC. Tensile results were inconclusive due to consistent fractures occurring outside the gauge lengths of the specimens.
Flexure strength was analyzed by conducting 3-point bend tests per ASTM D790. ASTM D790 calls for a larger than normal support span-to-coupon thickness ratio of 32:1 for high strength composites. The support span was therefore set to 42.6mm. The crosshead rate was calculated to be set constant at 1 mm/minute. Six samples were calculated in order to determine the scatter and consistency of the material’s mechanical properties. The mean flexure stress at maximum flexure load was 756.42 MPa with a standard deviation of 213.34 MPa. The mean maximum flexure load was 214.61 N. The Quantum composite data sheet reads that this material exhibits flexure strengths of 792 MPa, and tensile strengths of 421 MPa.