A metallurgical overview of Ti – based alloy in biomedical applications

Abstract

Titanium (Ti)-based alloys are prominently used in biomedical application. This review paper emphasizes on some of the important aspects of the Ti-alloys in terms of metallurgical aspects, manufacturing routes and biocompatibility. Two kinds of structure are reviewed namely dense and porous, both differs in terms of purpose and satisfies different needs. This advancement of materials and equipment helps to improve the quality of life for patients and alleviate their health problems. Metallic materials, mainly Ti-based alloys have been used commercially as bone implant owing to its promising mechanical properties, biocompatibility and bioactivity. The outmost important issue in manufacturing of this alloy is the impurity contents, specifically oxygen and carbon which contribute to decreasing in material performance of the alloy attributed from the formation of unwanted oxide compounds such as TiO2 and TiC. Another issue is the mismatch value of the Young’s modulus between the metallic implant and bone that result in stress shielding effect. The structure of Ti-based alloy is mainly comprised of α-phase, β-phase or a combination of both that result in variation of Young’s modulus ranging from 45 -110 GPa. Compared to α-phase Ti alloy, the β-phase rich alloys may exhibit lower value of Young modulus through the right processing technique. Therefore, the development of β-phase Ti-alloys has been researched progressively in line with the need of low Young’s modulus that suit for implant applications.