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While 3D printing allows manufacturers to create lightweight parts with complex shapes that traditional methods cannot, many 3D-printed components still lack the strength and reliability needed for high-performance applications. Oleksandr Kravchenko, Ph.D.’s research aims to develop stronger, lighter and more reliable 3D-printed composite parts that could be used across industries such as aerospace, military and automotive manufacturing.

Dr. Kravchenko, an associate professor in ��������’s Department of Mechanical and Aerospace Engineering, has received a $400,000 National Science Foundation (NSF)  to support a three-year project building on the manufacturing process he patented with former doctoral student Jimesh Bhagatji, Ph.D. (M.S. ’22, Ph.D. ’25). The technology incorporates a technique known as Hot Powder Bed Compaction (HPBC), which uses heat and pressure in a surrounding powder bed to improve the strength and quality of 3D-printed composite parts without the need for traditional molds.

The challenge comes from the layer-by-layer printing process, which leaves tiny air pockets and weak bonds between layers that can reduce the part’s performance.

Dr. Kravchenko’s approach starts with a standard 3D-printed part covered in thermoplastic layers containing reinforcing fibers and then placed in a bed of fine powder. As the powder is heated, it transfers heat and applies pressure from all directions. The heat melts the plastic, while pressure helps close tiny air pockets and strengthen the bonds between printed layers. The reinforcing fibers help control the viscosity of the melted plastic to ensure the part’s shape is preserved throughout the process.

The result is a stronger, denser component with performance closer to parts made through traditional compression molding, a manufacturing process that uses expensive metal molds to produce high-strength composite components.

The key to the technique is controlling temperature and viscosity. If the material becomes too fluid, it can lose its structure; if it does not flow enough, the layers will not fully fuse. By finding the right balance, the process can improve strength while maintaining the lightweight, complex designs that make 3D printing valuable.

Although Dr. Kravchenko has been developing the concept for several years, one of the first prototypes came from a senior design project by a group of engineering technology students. The team used the process to create a lightweight, 3D-printed clutch and accelerator pedal for a Formula race car. Tested under 79 pounds of force (350 newtons) to simulate racing conditions, the pedals matched the strength of the original aluminum parts while reducing weight by 43%.

Building on that student proof-of-concept, the NSF-funded research will help the team refine the process for larger, more complex components across various advanced thermoplastic composites. One ongoing challenge is that parts shrink during processing depending on their shape and printing configuration. To address this, University researchers will develop multi-physics computer simulations to predict shrinkage and track how heat and pressure move through the powder into the printed part.

The team will explore different temperatures, pressures and heating times to determine how those settings affect strength, stiffness, dimensional accuracy, internal stresses and the material’s microscopic structure.

“We really need to understand the reproducibility and multi-physics that control the shrinkage,” Dr. Kravchenko said. “It’s the science that has to be understood.”

“Some thermoplastics we are looking at need to be processed at about 350° C, which is representative of the materials used by the aerospace industry,” Dr. Kravchenko said. “The best part is that with HPBC you can turn your printed part into a truly structural-grade component using the existing Fused Deposition Modeling ( FDM) technology used in most of the commercial 3D printers today.”

The project will also provide undergraduate and graduate students working in the University’s  with hands-on research experience in advanced manufacturing and materials engineering.

Dr. Kravchenko’s work starts at ��������, but it has the potential to reach far beyond campus to develop new technologies in aerospace, automotive and defense, making a real-world impact by creating new possibilities in manufacturing.