Method for preparing damage-resistant 3D-printed ceramics via interior-to-exterior strengthening and toughening

Despite their high strengths and moduli, the inherent brittleness of ceramics restricts their ability to resist fracture upon impact. Designing special structures can toughen ceramics and expand their application realm; however, the ceramic strength is sacrificed. To address this problem, a damage-resistant ceramic process involving both interior and exterior strengthening and toughening is proposed. In this method, a buried combustion method (BCM) was implemented while debinding alumina (Al2O3) green bodies, and a coating method (CM) was used after sintering Al2O3 parts. Experimental results show that an increase of 259% in ultimate compressive stress and an increase of 161% in energy absorption compared with untreated Al2O3 parts were achieved by adopting the BCM and CM methods. In addition, a finite-element modeling method was used to study fracture mechanisms, and molecular dynamic simulations were implemented to provide insight into the strengthening and toughening mechanisms at the atomic level. [Display omitted] •An interior-to-exterior method to strengthen and toughen ceramics was developed.•Buried combustion method and coating method could suppress crack propagation.•Finite element modeling method was carried out to study fracture mechanisms.•Molecular dynamics were used to study strengthening and toughening mechanisms.