Improved Tribocorrosion Behavior Obtained by In-Situ Precipitation of Ti2C in Ti-Nb Alloy

Author(s)

Goncalves, Vinicius Richieri Manso ; Caha, Ihsan ; Alves, Alexandra Cruz ; Toptan, Fatih ; Rocha, Luis Augusto

• Document type: Journal article
• Source: METALS; v. 12, n. 6, p. 17-pg., 2022-06-01.

Abstract

Novel in-situ Ti-based matrix composites (TMCs) were developed through the reactive hot pressing of Ti + NbC powder blends. Due to the chemical reaction that occurred in the solid-state during processing, the produced samples were composed of an Nb-rich beta-Ti phase that formed a metallic matrix along with Ti2C as a reinforcing phase. By employing different proportions of Ti:NbC, the phase composition of the alloys was designed to contain different ratios of alpha-Ti and beta-Ti. The present work investigated the corrosion and tribocorrosion behavior of the composites, compared to unreinforced Ti, in a phosphate-buffered solution (PBS) at body temperature. Corrosion tests included potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Tribocorrosion tests were carried out using a ball-on-plate tribometer with sliding performed at open circuit potential (OCP) and under anodic potentiostatic conditions. Results showed that the stabilization of the beta phase in the matrix led to a decrease in the hardness. However, the formation of the in-situ reinforcing phase significantly improved the tribocorrosion behavior of the composites due to a load-carrying effect, lowering the corrosion tendency and kinetics under sliding. Furthermore, localized corrosion was not observed at the interface between the reinforcing phase and the matrix. (AU)

• FAPESP's process: 19/07953-0 - In-situ synthesis of functionally graded Ti-based matrix composites by low-cost liquid metallurgical route
• Grantee: Vinícius Richieri Manso Gonçalves
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 17/24300-4 - A new concept for producing graded bio-functionalized materials for orthopaedic implants
• Grantee: Luís Augusto Sousa Marques da Rocha
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/00746-6 - Development and characterization of in-situ Ti-Nb matrix composites for biomedical applications
• Grantee: Vinícius Richieri Manso Gonçalves
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)