Abstract
An approach is presented for determining the melt processing conditions of high temperature amorphous thermoplastics, specifically carbon fiber reinforced polyetherimide (PEI), for Big Area Additive Manufacturing (BAAM). PEI is a high performance thermoplastic that is attractive for various high temperature applications in the automotive and aircraft industry. For PEI to be processed successfully with BAAM, it must be stable over a range of temperatures and print conditions to ensure the final part possesses the desired strength and modulus. Under this approach, thermal properties are first analyzed to identify the lower and upper operating limits for the polymer and then extensive rheological characterization is carried out at selected temperatures within these bounds. This study investigates the effect of temperature, fiber loading, and processing environment on rheology in order to identify suitable process parameters for extruding carbon-fiber reinforced PEI on BAAM.
