Development of Investment Casting Method for Production of Metal Foams for Tissue Engineering

Abstract

Ideal biomaterials for bone tissue regeneration are bone-mimicking structures that present a fully interconnected porous structure, have similar mechanical properties to bone, and exhibits a specific biodegradation behavior that is at the same rate as adjoining cell growth. Metals have high wear resistance, ductility, impact strength, and strain energy absorption capacity compared to other materials, which makes them suitable candidates for tissue engineering scaffolds. Magnesium and zinc are of interest for bone tissue regeneration for their biocompatibility and mechanical properties close to human bone. A newly developed process, presented in this thesis, for the creation of porous magnesium and zinc scaffolds, using rapid prototyping, developing a ceramic mold, and an investment casting procedure, shows promise for the requirements of the scaffold. This process was able to produce zinc scaffolds with pore sizes varying from 1000 µm to 2500 µm. These scaffolds had pore and strut sizes within 5% error of their CAD design. Lastly, the scaffolds produced had mechanical properties within the range of human cancellous bone.