Microstructural Evolution, Mechanical Properties, and Preosteoblast Cell Response of a Post-Processing-Treated TNT5Zr β Ti Alloy Manufactured via Selective Laser Melting

Abstract

A Ti–34Nb–13Ta–5Zr (TNT5Zr) β Ti alloy with a high strength-to-modulus ratio has been developed, showing its potential to become another candidate material in load-bearing implant applications. This work mainly investigates the microstructural evolution, mechanical properties, and biocompatibility of a post-processing-treated TNT5Zr alloy manufactured via selective laser melting (SLM). Transmission electron microscopy observation shows the existence of the single beta grain matrix and alpha precipitates along the grain boundary in the SLM + HIP manufactured TNT5Zr alloy (TNT5Zr-AF + HIP), and ellipsoidal nano-sized intragranular α″ precipitates (approx. 5–10 nm) were introduced after the subsequent low-temperature aging treatment. The precipitation strengthening enables the SLM + HIP + aging manufactured TNT5Zr (TNT5Zr-AF + HIPA) alloy to show a comparable ultimate tensile strength (853 ± 9 MPa) to that of the reference material (Ti64-AF + HIP, 926 ± 23 MPa). Including the inferior notch-like surface of the test pieces, the slip-band cracking that occurs in this ductile TNT5Zr-AF + HIPA alloy is regarded as the main factor in determining its fatigue strength (170 MPa). In vitro short-term biocompatibility evaluation reveals almost no significant difference in the preosteoblast viability, differentiation, and mineralization between TNT5Zr-AF + HIPA and the reference biomaterial (Ti64-AF + HIP).

Advanced Ti–Nb–Ta Alloys for Bone Implants with Improved Functionality

“…Biomedical β-type Ti alloys are typically formed in binary system Ti-Nb [7,13,15], ternary systems Ti-Nb-Ta [16][17][18], Ti-Nb-Zr [10], and Ti-Ta-Zr [19], and quaternary systems such as Ti-Nb-Ta-Zr [8,9,11,20] and Ti-Nb-Zr-Sn [21,22]. Entirely β-type Ti alloys may have a Young's modulus as low as 33 GPa [21], while Ti-6Al-4V has a Young's modulus of approximately 114 GPa [23].…”

Effect of Glucose Contents on Electrochemical Corrosion Behavior of Ti/ZrO2 Brazing Joint in SBF

“…In recent years, the application of ZrO 2 ceramic has grown rapidly. , The ZrO 2 ceramic has the advantage of high strength, wear resistance, corrosion resistance, and excellent biocompatibility, so that it is generally used in aerospace, metallurgy, biological medicine, etc. − However, the cutting performance of ceramics is poor, and it is difficult to make complex structural parts. The admirable properties of titanium alloys, such as high toughness, excellent biocompatibility and great corrosion resistance, make them appropriate as medical and aerospace materials. − Therefore, the connection between ceramic and titanium alloys could give play to their excellent performance, thus meeting the performance requirements of implantable devices. The titanium/ceramic joints have been used in implantable devices such as artificial retina, implantable pacemakers and microstimulators .…”

Selective Polyetheretherketone Implants Combined with Graphene Cause Definitive Cell Adhesion and Osteogenic Differentiation

“…[1][2][3] The most widely used bone repair biomaterials are metal materials with high elastic modulus such as titanium and its alloys. 4,5 However, the high elastic modulus of metal differs significantly from that of natural bone. 6 This mismatch will cause a stress shielding effect: the metal implant bears a major load when the bone and the implant are simultaneously stressed, which may lead to adjacent bone atrophy or implant failure.…”

“…6 This mismatch will cause a stress shielding effect: the metal implant bears a major load when the bone and the implant are simultaneously stressed, which may lead to adjacent bone atrophy or implant failure. 5,7 In addition, metal implants may interact with body fluids and undergo electrochemical corrosion, and metal ions can act as haptens and cause an inflammatory response. [8][9][10] Fabricating a bone implant material with an elastic modulus matching that of natural bone would be ideal to address these problems.…”