Production of Low Coefficient of Thermal Expansion Composite Tooling Manufactured Via 3D Printing

Additive manufacturing enables the ability to produce composite tooling molds in a rapidly and cost effective manner. This work has produced low coefficient of thermal expansion composite tooling based on Invar, ceramics and metal-ceramic composites that are functional in the temperature range of 180°C. Here, four main approaches have been considered. The first approach consisted on using a binder jetting technology to 3D print sand molds to cast molten Invar to produce tooling. The second approach consisted on printing a mold based on both silica and zirconia sand and infiltrating them with a polymer to yield a robust tooling. The third approach was based on transforming a SLA printed ceramic mold into a metal-composite system. The fourth technology was based on a Direct Energy Deposition System for attaching Invar upon a steel molding structure. This last approach could represent a promising technology for producing low cost composite tooling since only a small layer of Invar would be added to a non-expensive substrate. The results have shown that the aforementioned processes have successfully resulted on low CTE tooling molds and successful composite materials.