Polycrystalline micropillars by a novel 3-D printing method and their behavior under compressive loads

We present an entirely new method of bottoms-up fabrication of polycrystalline micropillars using direct printing and sintering of nanoparticles in 3D and study their behavior under compression for different microstructures. The pillars showed brittle behavior with higher effective modulus for small grain sizes with high porosity, while highly ductile behavior with a lower effective modulus and larger grain sizes but low porosity. These unusual trends are explained by a porosity model. The results point to a novel method of fabricating micropillars with different microstructures to study fundamental materials science of polycrystalline materials at micro to meso-length scales.