3D printing technology has grown rapidly over the course of the last decade. Researchers and engineers have designed increasingly complex parts and more people have access to 3D printers than ever before. Brett Compton, Assistant Professor in Mechanical Engineering at the University of Tennessee, leads research on understanding more about how a 3D printer processes materials. The team works to create better materials with a greater variety of useful properties; stronger, stiffer, more durable.  

    Compton has already created printed epoxy composites that are 5-10 times better than  other polymer materials currently available from commercial 3D printers. This research is different than many other varieties of additive manufacturing research, in that the focus is on understanding how the unique features of the additive manufacturing process can be utilized to create unique hybrid structures that result in better mechanical and functional properties. In this lab, researchers create a wide variety of materials with infinite practical potential; everything from high temperature ceramics to flexible elastomeric foams.

    By thinking outside of the box with epoxy composites, high temperature ceramics and unique, graded cellular materials (mostly hollow with materials partially filling space), Compton creates materials that mimic nature and have the potential to enhance our lives. This research will give design engineers greater control over material properties than has ever existed before.

The future of this research includes:

• 3D printing of high temperature ceramic composites from polymer precursors: Hybrid and inorganic polymers – like silicone rubber and similar materials – are comprised of silicon and other elements that replace carbon in the polymer chain. These polymers can be converted to ceramic materials by heating to extremely high temperatures in an absence of oxygen. The resulting ceramics (silicon carbides and silicon nitrides) are extremely hard and temperature resistant. New methods are being developed to modify existing hybrid polymer resins to enable them to be 3D printed and subsequently converted to high temperature composite materials. Success in this area could enable new ceramic composite components with increased toughness, strength, hardness, and temperature resistance. Potential applications include new armor systems to protect soldiers and vehicles, new lightweight brake rotors with better thermal management, and new engine components for better fuel efficiency.

• Novel ceramic-metal hybrids for high-strength, patient-specific maxillofacial implants: The treatment of bone defects in the cranial and maxillofacial sections of the skull caused by extreme trauma or tumor removal is a common clinical problem. Current approaches to treatment can lead to donor site morbidity, thermal sensitivity, inflammation, and implant rejection. This project focuses on the development of new 3D printing methods and materials that enable the creation of unique ceramic-metal hybrid materials that combine the strength of metallic parts with the biocompatibility of bioceramic materials.  

• Ultra-lightweight composite lattice structures inspired by bird bones: The structure of wood, plant stems, and avian bones provide inspiring examples of multi-scale cellular materials that are tailored to a specific set of functions. Drawing from these natural structures, new concepts in cellular materials are being explored that combine lattice architecture, fiber-reinforced polymer composites, stochastic foams, and novel 3D printing methods to create ultra-lightweight lattice materials with unprecedented properties.

Designs created on computers cannot always come to life with 3D printers. Traditionally, the products made by 3D printers are relatively flimsy and don’t have a great deal of strength and durability. Brett Compton is creating new hybrid materials with never-before-seen cellular structures and multi-material architectures to enhance the potential of 3D printing. This research can be used to create better biomedical implants, stronger parts for engineers, more efficient automotive protection systems, and superior body armor modeled after the biological defenses of other species.