Artificial Bone and Teeth through Controlled Ice Growth in Colloidal Suspensions

TL;DR

This paper presents a method to create porous ceramic structures mimicking bone and teeth by controlling ice growth in colloidal suspensions, enabling tailored architecture and improved mechanical properties for biomedical applications.

Contribution

It introduces a controlled ice growth technique in ceramic slurries to produce multilayered porous structures for artificial bone and teeth, with insights into solidification physics.

Findings

Porous alumina and hydroxyapatite structures with controlled architecture.

Infiltration with second phases yields nacre-like composites with enhanced properties.

Understanding ice growth dynamics aids in tailoring material properties.

Abstract

The formation of regular patterns is a common feature of many solidification processes involving cast materials. We describe here how regular patterns can be obtained in porous alumina and hydroxyapatite (HAP) by controlling the freezing of ceramic slurries followed by subsequent ice sublimation and sintering, leading to multilayered porous ceramic structures with homogeneous and well-defined architecture. These porous materials can be infiltrated with a second phase of choice to yield biomimetic nacre-like composites with improved mechanical properties, which could be used for artificial bone and teeth applications. Proper control of the solidification patterns provides powerful means of control over the final functional properties. We discuss the relationships between the experimental results, ice growth fundamentals, the physics of ice and the interaction between inert particles and the solidification front during directional freezing.