3D-printed washout tooling for ultralightweight composites

In this presentation we will explore a case study for the manufacturing of a Type 5 hydrogen tank made from carbon fiber. It utilizes binder jet 3D printing to create a washable mandrel which supports the fabrication of this tank using carbon fiber filament winding. . The specific broader implication is on complex, lightweight composites for defense, aerospace and automotive.
The tank had to be manufactured in a single piece with carbon fiber composite. The design of the tank is as such that the tooling on which the carbon fiber is woven cannot be removed afterwards, and therefore a water soluble tooling was developed using binder jetting 3D printing.
The carbon fiber composite manufacturing process offers several challenges to the 3D printed element. The parts have to be strong enough to survive the handling and carbon fiber robotic weaving process. Secondly the parts have to be large: around 2 feet in length and 8 inches in diameter. Thirdly the surface finish has to be of high gloss to offer a quality inner surface. After applying the carbon fiber layup, parts go to the autoclave where they are exposed to significant pressure and cured at above 350 Fahrenheit. Then, after that process, the parts are exposed to water, the tooling dissolves and the part remains.
This process with a material that offers quality surfaces and is able to withstand pressure and heat is highly novel and has use cases for the aerospace industry, the defense industry (lightweight drones!), automotive and boating – practically anywhere where lightweight, complex composites are in high demand.
The purpose of the presentation is to show the full process and engage with the audience on topics such as surface quality, part dimensions and applications in their industry.