Development of bio-compatible refractory Ti/Nb(/Ta) alloys for application in patient-specific orthopaedic implants. (September 2018)

• Record Type: Journal Article
• Authors: Weinmann, M.; Schnitter, C.; Stenzel, M.; Markhoff, J.; Schulze, C.; Bader, R.
• Is Part Of: International journal of refractory metals & hard materials. Volume 75(2018)
• Page Start: 126
• Page End: 136
• Publication Date: 2018-09
• Subjects: Additive manufacturing -- Titanium -- Niobium -- Tantalum -- Medical implant -- Biocompatibility; Heat resistant alloys -- Periodicals; Refractory materials -- Periodicals; Metallography -- Periodicals; Alliages réfractaires -- Périodiques; Matériaux réfractaires -- Périodiques; Métallographie -- Périodiques; Heat resistant alloys; Metallography; Refractory materials; Periodicals; Electronic journals; 669.73
• DOI: 10.1016/j.ijrmhm.2018.03.018
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: Orthopaedic implant materials are exposed to high mechanical loading. Conventional materials based on stainless steel or cobalt-chromium alloys display adequate mechanical strength, but also toxicological concerns due to release of toxic or allergenic elements (particles or ions) resulting in inflammatory reactions in the adjacent tissues. Metal alloys based on titanium, tantalum and niobium represent higher biocompatibility with appropriate mechanical properties for avoiding stress-shielding and consecutive implant loosening. Application of specifically designed spherical Ti/Nb(/Ta) alloy powders in additive manufacturing, i.e. 3D metal printing processes such as selective laser melting (SLM) or electron beam melting (EBM), enable the production of components with a high degree in freedom of design. Accordingly, SLM or EBM of Ti/Nb(/Ta) alloys offer the possibility to fabricate patient-specific orthopaedic implants. The present paper gives an overview on the development of bio-compatible Ti/Nb(/Ta) alloys especially designed for application in 3D metal printing. Furthermore, the additively manufactured 3D structures are mechanically tested and the influence of differently grained alloy powders and bulk parts on the viability and proliferation of human cells (fibroblasts, osteoblasts) are examined. Highlights: Various Nb and Ti/Nb compositions have been studied for their applicability as implant materials and compared with Ti-6Al-4V. For the first time, additively manufactured Ti-42Nb has been investigated i.e. printed by means of SLM. Mechanical properties (elasticity) have been determined and in-vitro cell tests performed. It has been found that sintered and SLM-printed Ti-42Nb has significantly improved elasticity compared with Ti-6Al-4V and advantageous cell tolerance, i.e. increased biocompatibility with osteoblasts and fibroblasts.