Work

Alumina-based interpenetrating phase composites by binder jetting: effects of powder multimodal distributions on porous preforms formation and copper-infiltrated composite performance

Year: 2025

Type: article

Abstract: The development of interpenetrating phase composites via binder jetting offers a promising route for fabricating architected ceramic–based systems with tailored microstructures and multifunctional properties. This study investigates the influence of multimodal particle size distributions of spheroidized alumina powders on the formation, sintering behaviour, and copper infiltration performance of porous ceramic preforms. Six distinct feedstocks with varying multimodality were characterized in terms of flowability, spreadability, and packing efficiency. The resulting green and sintered preforms were evaluated for porosity morphology and densification kinetics by geometrical measurements and computed tomography, revealing feedstock-dependent voids architectures. These networks control capillary-driven infiltration dynamics and the formation of complex copper–alumina oxide phases, including spinel and delafossite with twinning mechanisms. CALPHAD simulations corroborated the experimental findings, elucidating the thermodynamic pathways of phase evolution under varying oxygen activities. Mechanical testing demonstrated that composites derived from sintered preforms exhibit superior hardness and wear resistance with a reduction of the friction coefficient of ~25 % compared to those produced from green preforms, attributed to enhanced alumina content and refined oxide phase distribution. These results underscore the pivotal role of powder multimodality and preform processing in dictating the hierarchical structure and performance of printed ceramic–based composites, offering new insights for the design of advanced materials with tunable properties and complex geometries. • Multimodal PSDs tailored alumina flowability and green density in binder jetting. • Porosity architectures determined sintering and copper infiltration efficiency. • Infiltration in air formed binary and mixed (spinel, delafossite) oxide networks. • Hardness and wear resistance depends on preforms processing and oxides nature. • CALPHAD modelling can predict oxides formation upon cooling from Al 2 O 3 interfaces.

Source: Materials Characterization

DOI: 10.1016/j.matchar.2025.115651

Authors: Marco Mariani, Francesco Bertolini, Lorenza Fabiocchi, Elisa Mercadelli, Carmen Galassi, Nora Lecis

Institutions: Politecnico di Milano, Institute of Science, Technology and Sustainability for Ceramics, National Research Council

Language: English

Topic: Additive Manufacturing and 3D Printing Technologies

Subfield: Automotive Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: hybrid

Estimated APC paid: $3,320