Dense and strong ceramic composites via binder jetting and spontaneous infiltration

The objective of this study is to test the feasibility to produce fully ceramic composites (i.e., without containing any metal phases) by binder jetting of alumina preforms and spontaneous infiltration by copper in air. Alumina powders of different particle sizes (submicron and micron) were used as the feedstock for binder jetting. Afterward, standard post-processing steps were first applied, including curing, depowdering, debinding, and sintering. The sintered specimens were then spontaneously infiltrated with copper in air. The sintered specimens made with both powders had high porosity and poor mechanical properties. The infiltrated specimens made with both powders approached full density, and their mechanical properties were significantly improved. The compressive strength of 826.0 MPa and the flexural strength of 317.5 MPa achieved in this study are greater than those of any alumina-based specimens made via binder jetting followed by sintering and/or infiltration in the literature.

Automated summary

The objective of this study was to evaluate the feasibility of producing metal-free fully ceramic composites using binder jetting of alumina preforms and spontaneous infiltration by copper in air. Different particle sizes of alumina powders were used as feedstock for binder jetting, followed by standard post-processing steps. The sintered specimens were then infiltrated with copper, resulting in improved mechanical properties compared to the porous sintered specimens. The compressive strength of 826.0 MPa and flexural strength of 317.5 MPa achieved in this study exceed those reported in the literature for binder jetting and/or infiltration of alumina-based specimens.