Description |
Syntactic foams are a low-density composite material that are used in a wide range of industries. Wide usage of these foams in industry is due to the ability to customize their mechanical, thermal, acoustic, and electrical properties. As new foams are developed, it is important to develop a mechanical test for the determination of the batch quality. In this thesis, a mechanical test is developed and assessed for determining the batch quality of a glass-microsphere syntactic polyurethane foam. The mechanical test must produce low variability within replicate specimens, be easy to perform, and adequately identify differences between batches of the foam. Initial mechanical testing of the foam was completed to characterize its stiffness and strength properties in tension, compression, and shear. The tension and compression moduli were determined using standard ASTM test methods. The shear modulus was determined using an asymmetric four point bend test. The material properties of the foam were then used in a finite element analysis to develop tension, compression, and shear elastic-plastic models of the foam. These models were used to evaluate test variations for the determination of batch quality of the foam. The shear punch test was determined to be an attractive candidate for the determination of batch quality of the foam. Varying geometries of the shear punch test were analyzed and tested to determine the best in situ test configuration for batch quality testing of the foam. The results of this investigation show that the shear punch test method is an easy to perform mechanical test for the determination of batch quality of a glass-microsphere syntactic polyurethane foam. |