OUT-OF-AUTOCLAVE COMPOSITES MANUFACTURING WITH ELECTRICALLY HEATED CARBON FOAM TOOLING

摘要

Touchstone Research Laboratory, Ltd. has developed an Out-of-Autoclave (OOA) composites manufacturing process with an electrically self-heated carbon foam tooling system. Electrically Heated Tooling (EHT) utilizes a coal-based carbon foam (CFOAM~?) core that serves as the tool substrate and the heating source for a composite mold. Thermally uniform tooling surface heating results from current flowing through the foam. This approach to self-heated tooling overcomes thermal uniformity challenges associated with both discrete resistive heating elements and circulating fluid tools that have restricted widespread adoption of self-heated tooling in the composites industry. Carbon foams have added benefit for tooling because they are inexpensive, machinable, and lightweight; have low thermal expansion and high use temperatures.rnPresented in this paper are the results of studies funded by both the Missile Defense Agency (MDA) and the National Aeronautics and Space Administration (NASA), which found that a thermally uniform tooling surface is feasible with a resistively heated carbon foam tool. These results are based on critical factors such as tool geometry and joining techniques. This paper will focus on the fabrication steps to build flat and complex geometry tools as well as on thermal uniformity measurements and cured composite laminate results of carbon fiber reinforced out-of-autoclave epoxy prepreg systems.