Effects of elements W and C on microstructure and wear property of γ-TiAl surface alloying layer

Abstract

To solve the poor tribological property of the c-TiAl alloy, the duplex treatment of plasma carburisation on plasma alloying c-TiAl with tungsten was conducted by double glow plasma surface alloying technique. The results indicated the alloying layer consisted of TiC and W 2 C phase, metallurgically adhered to the substrate. In terms of the H/E and H 3 /E 2 ratios, the duplex treated specimen was nearly three times larger than the untreated specimen. The wear property of the specimens was tested on a pin-on-disk tribometer by rubbing against Si 3 N 4 ceramic ball. The wear rate of the duplex-treated specimens is 1?056610 24 mm 3 N 21 m 21 , which is only 25?9% of that of the untreated specimens. The relationship between alloying layer mechanical property and wear resistance indicates that the carbide phase formed within the alloying layer contributes to the improvement of the wear performance.

Microstructure, nano-mechanical characterization, and fretting wear behavior of plasma surface Cr-Nb alloying on γ-TiAl

“…Moreover, the hardness and elastic modulus ratio also constitutes a parameter for the -TiAl wear resistance measurements [37]. The H/E was the resistance of elastic strain to failure and the H 3 /E 2 represented the resistance to plastic deformation of the -TiAl before and after Cr-Nb co-alloying [37,38]. As shown in Fig.…”

“…As shown in Figure 7, H/E and H 3 /E 2 of Cr-Nb co-alloyed coating were significantly higher than that of the γ-TiAl, indicating better resistance to elastic strain failure and better resistance to plastic deformation. 37,38 The Cr-Nb co-alloyed coating with high resistance to plastic deformation had strong deformation adaptability and ability to absorb deformation energy, resulting in better cracking and delamination resistance fretting wear process. Hence, until 7500–10,000 fretting cycles, the wear scar of γ-TiAl after Cr-Nb alloying did not show any delamination comparing with the γ-TiAl substrate.…”

A study on tribological behavior of double-glow plasma surface alloying W-Mo coating on gear steel

“…Although hardness has long been regarded as a primary material property to evaluate the wear resistance of materials based on classical theories of wear, many researchers have proposed that the elastic strain to failure (H/E) and the plastic deformation resistance factor (H 3 /E 2 ) are more suitable parameters for predicting wear resistance than hardness alone [24][25][26].…”

Deformation mechanism and tribological behavior of hydrogen-free carburized layer on Ti-6Al-4V alloy

“…Our previous experimental study has demonstrated that DGP surface treatment technology was a useful method to improve the abrasion performance of titanium alloys (Xu et al , 2007, 2017a; Qiu et al , 2015; Duan et al , 2015). Zhang et al (2004) found that the transformation of microstructure and hardness on the surface of Ti-6Al-4V alloy during the carburizing process brought out the evident improvement of wear resistance.…”