Additive manufacturing of titanium and titanium alloys for biomedical applications

Abstract Metallic biomedical implants comprise almost over 95% of the orthopedic and dental implant market worldwide. A steady increase in surgical interventions using metallic implants is continuing over the years to improve the quality of life of our ageing population. Among different material options for implants, titanium (Ti) and its alloys are very popular due to their excellent biocompatibility and proven mechanical properties, namely fatigue resistance and high strength-to-weight ratio. In recent years, innovation in manufacturing technologies toward biomedical implants, particularly load-bearing implants, have initiated excitement toward novel designs and design modifications. Among different manufacturing technologies and technological innovations, additive manufacturing or 3D Printing is making the most significant impact. Several additive manufacturing based technologies exist, although the focus of this review is to discuss three key approaches and provide examples of work performed using those technologies along with their potential impact. The fabrication technologies discussed here are primarily laser and electron beam based additive manufacturing using both powder bed and directed energy deposit techniques. We have also briefly discussed challenges as well as future trends in the field.