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

Metals

Ihsan Çaha¹  Fatih Toptan¹  Alexandra Cruz Alves¹  Vinícius Richieri Manso Gonçalves²  Luís Augusto Rocha² 

[1] Center for MicroElectroMechanical Systems (CMEMS-UMinho), University of Minho, 4800-058 Guimarães, Portugal;Department of Physics, School of Science, São Paulo State University (UNESP), Bauru 17033-360, Brazil;

关键词: Ti-based composites;    niobium carbide;    powder metallurgy;    tribocorrosion;   

DOI  :  10.3390/met12060908

来源: DOAJ

【 摘 要 】

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 β-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 α-Ti and β-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 β 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.

【 授权许可】

Unknown