Biomedical Applications Of 3D Printed Titanium Alloys

The use of orthopaedic biomaterials has increased dramatically over the last few years as the population ages and patients wish to maintain the same level of activity and quality of life. Driven by the huge demand for clinical orthopaedic biomaterials, bone tissue engineering has developed rapidly and a range of orthopaedic biomaterials have been investigated and designed. Fe- and magnesium-based biomaterials are widely used with the aid of 3D technology. Titanium-based biomaterials have high strength, low specific modulus and better biocompatibility than Fe- and magnesium-based biomaterials and show a competitive and unique advantage among orthopaedic biomaterials.

3D printed titanium-based biomaterials can be customised to suit individual needs, allowing not only the fabrication of complex structures but also unparalleled advantages in terms of cost, manufacturing cycle time and personalisation, allowing for significant development of the technology for orthopaedic, dental and cardiovascular applications. However, the technology still faces many challenges, such as how to balance the relationship between porous bone growth and mechanical properties, the choice of additive manufacturing technology, and parameter optimisation.

The analysis and summary of 3D printed titanium alloy technology have led to the following conclusions.

(1) Different 3D printing technologies differ in terms of thermal scan speed, power supply power and deposition rate. Compared to conventional processes, 3D printing preparation processes have typical characteristics of rapid heating and cooling, and precise control of process parameters is required to obtain high-quality and reliable parts;

(2) The topology of bone tissue is classified and described, and it is pointed out that one way to reduce the stiffness is to reasonably optimise the topology of porous bone substitutes, thereby reducing the difference in stiffness between the bone substitute and the host bone, thereby alleviating the problem of stress shielding.

(3) The influence of the characteristics of rapid heating and cooling on the tissue evolution of titanium alloys is analysed, and improvements in mechanical properties can be achieved by adjusting the two-phase composition and tissue morphology;

(4) The biocompatibility and osseointegration capabilities of porous titanium alloys after implantation are highlighted;

(5) 3D printed metals are only better developed through the development of powerful digital tools, such as machine modelling and machine learning combined with metallurgical knowledge bases.