Rapid Oxynitriding of Ti–6Al–4V Alloy by Induction Heating in Air

Abstract

In this study, a rapid oxynitriding technique based on induction-heating was developed for the titanium alloy Ti6Al4V, and its effects on surface characteristics of the alloy were investigated. The surface microstructures of the alloy were characterized by employing a scanning electron microscope, electron back-scatter diffraction, X-ray diffraction and nano-indentation tests. Induction-heating in air for 60 s caused the formation of a hardened layer on the Ti6Al4V alloy surface, which can be attributed to the diffusion of oxygen and nitrogen atoms. When water quenching was performed after heating, transformation to an acicular martensitic ¡A phase occurred, resulting in increased in substrate hardness. However, cracks were initiated at the surface of the oxynitrided alloy. The cracks were eliminated through fine particle bombarding treatment, whereas the hardened layer formed by the oxynitriding treatment remained. The obtained results thus indicate that the oxynitriding technique developed in this study can enhance the wear resistance and tensile strength of the Ti6Al4V alloy within a short period of time.

Combined Effect of Gas Blow Induction Heating Nitriding and Post-Treatment with Fine Particle Peening on Surface Properties and Wear Resistance of Titanium Alloy

“…11) Moreover, the authors also revealed that IH in air can form a hardened layer at the surface of Ti6Al4V alloy due to reaction with the elements contained in air. 12) These previous studies revealed that IH can accelerate the diffusion of elements surrounding the heated titanium.…”

Antibacterial effect on microscale rough surface formed by fine particle bombarding

“…Dry etching requires expensive devices and ancillary equipment, such as gas removal devices, which increase cost and limit the size of substrates. In our previous studies, we used fine particle bombarding (FPB) (Tamura et al 2021 ; Morita et al 2020 ; Ohue et al 2008 ; Morita et al 2013 ) to achieve microscale roughness. In FPB, a microscale rough surface is formed by bombarding fine particles, such as ceramics, onto a metal surface.…”