Coefficient of Thermal Expansion Test Report

A scale-up version of a fused deposition modeling (FDM) machine known as Big Area Additive Manufacturing (BAAM) has been developed in the Manufacturing Demonstration Facility (MDF) at the Oak Ridge National Laboratory. In this report, we present the coefficient of thermal expansion (CTE) of specimens manufactured with the BAAM system in directions parallel and perpendicular to the deposition direction. The CTE describes how the length of a material changes with a change in temperature at a constant pressure and it is computed as where ΔL denotes the change in length, $$CTE = \frac{^{\Delta L}/_{L_0}}{\Delta T}$$ L₀ the initial length, and ΔT is the change in temperature. The CTE values shown here were measured in a Thermo-Mechanical Analyzer (TMA). The tests were performed according the adaptation of the ASTM E831 provided by TA company instruments technical service using the TMAQ400.