Mitigating Distortion During Sintering of Binder Jet Printed Ceramics

Sintering increases the strength of binder jet 3D printed green bodies through densification, but with the potential cost of distortion due to creep. In this work, we determine how a reactive binder affects such distortion during sintering of titanium dioxide green bodies. The binder decomposes to form nanocrystalline interparticle necks during the early stages of the sintering process. We first characterize the decomposition of the reactive binder through thermogravimetry, differential scanning calorimetry, and x-ray diffraction. Next, we elucidate the effect of this precursor on the shrinkage of cylindrical parts using dilatometry experiments, and observe the deflection of sintering beams using in situ imaging. These experiments show that the precursor dramatically suppresses creep during sintering, demonstrating a potential solution for increasing the dimensional accuracy of the binder jet 3D printing process.