Additive manufacturing of composite tooling using high temperature thermoplastic materials

Composite materials have advantages over other traditional materials in terms of their light weight, specific strength, superior damping capacity, and corrosion resistance. Additive Manufacturing (AM) is a processing technique that can be used to significantly decrease the cost of manufacturing tools and composite molds from hundreds of thousands of dollars to thousands of dollars, and decrease the time of manufacturing tools from months to weeks or days. Conventional AM is very slow (∼ 16.5 cm³/hr), limited to small parts (< 0.03 m³), and uses expensive feedstock material (> $200/kg.). Big Area Additive Manufacturing (BAAM), on the other hand, enables the rapid manufacturing (> 16,387 cm³/hr) of large parts (> 5.7 m³) using relatively low cost feedstock. In this process, thermoplastic-reinforced composites can be used to fabricate large complex geometry components. This article is an attempt to investigate using the BAAM process to fabricate high temperature composite tooling. The BAAM system located at Oak Ridge National Laboratory's (ORNL) Manufacturing Demonstration Facility (MDF) has been used to manufacture a new generation of in-autoclave tools that can be used to fabricate various aerospace composite parts. Materials that are capable of withstanding elevated temperatures, namely Polyphenylene sulfide (PPS) with variations in high carbon fiber loading (i.e. 40 %, 50 % and 60 % by weight), were investigated. In addition to printing composite molds (i.e. tools), thermal and mechanical data has been collected and analyzed for the selected materials.