Elastic characterization of PEEK/IM7 using coefficients of thermal expansion

Three-dimensional elastic properties of a PEEK/IM7 unidirectional lamina are determined by an approach using laminate coefficient of thermal expansion (CTE) measurements and two known elastic constants. Specific relationships required to apply the technique and generate material elastic properties are derived from the general equations presented by the authors in a previous publication. The investigation emphasizes the feasibility and practical aspects of using CTE data to determine elastic properties. The room temperature elastic constants determined, based on measured CTEs, are compared with available data from the literature, obtained according to ASTM standard techniques. The approach, based on the CTE measurements, plus unidirectional tensile tests, allows the determination of all of the elastic constants, including the through-thickness Poisson's ratio ν 23, which is not commonly quoted.