Properties of Titanium Foams for Biomedical Applications

Abstract Titanium foams are presently used in various load bearing orthopedic applications. Such foams are characterized by an open network of porosity with high surface area. This paper presents the structure, microstructure, and properties of titanium foams produced with a powder metallurgy process. Fully porous CpTi and Ti6Al4V cylinders and CpTi foam coating on CpTi and Ti6Al4V substrates were produced and characterized. The microstructure of the foam cell walls is representative of annealed CpTi and Ti6Al4V. Alloying elements and oxygen in solution increase the mechanical strength of the foams but lower their ductility. Ductility affects the fatigue life of the material. When CpTi foam is bonded to Ti6Al4V substrates, migration of alloying elements in the foam cell walls is observed. Good metallurgical bonding is created between the coatings and the dense substrate and shear strength above the requirements of the FDA guidelines are obtained.