Microstructure and Wear Behavior of Ti-xFe-SiC In Situ Composite Ceramic Coatings on TC4 Substrate from Laser Cladding

Xiaojun Zhao; Peize Lyu; Shenqin Fang; Shaohao Li; Xiaoxuan Tu; Penghe Ren; Dian Liu; Lyuming Chen; Lairong Xiao; Sainan Liu

doi:10.3390/ma17010100

Microstructure and Wear Behavior of Ti-xFe-SiC In Situ Composite Ceramic Coatings on TC4 Substrate from Laser Cladding

Materials (Basel). 2023 Dec 24;17(1):100. doi: 10.3390/ma17010100.

Authors

Xiaojun Zhao^{1

2}, Peize Lyu¹, Shenqin Fang¹, Shaohao Li¹, Xiaoxuan Tu¹, Penghe Ren¹, Dian Liu¹, Lyuming Chen¹, Lairong Xiao^{1

2}, Sainan Liu³

Affiliations

¹ School of Materials Science and Engineering, Central South University, Changsha 410083, China.
² Key Laboratory of Non-Ferrous Metal Materials Science and Engineering, Ministry of Education, Central South University, Changsha 410083, China.
³ Center for Mineral Materials, School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China.

Abstract

Titanium alloys are widely used in various structural materials due to their lightweight properties. However, the low wear resistance causes significant economic losses every year. Therefore, it is necessary to implement wear-resistant protection on the surface of titanium alloys. In this study, four types of in situ composite ceramic coatings with two-layer gradient structures were prepared on a Ti-6Al-4V (TC4) substrate using laser cladding. In order to reduce the dilution rate, a transition layer (Ti-40SiC (vol.%)) was first prepared on TC4 alloy. Then, a high-volume-fraction in situ composite ceramic working layer (Ti-xFe-80SiC (vol.%)) with different contents of Fe-based alloy powder (x = 0, 5, 10 and 15 vol.%) was prepared. The working surface of Ti-40SiC (TL) exhibited a typical XRD pattern of Ti, TiC, Ti₅Si₃, and Ti₃SiC₂. In comparison, both Ti-80SiC (WL-F0) and Ti-5Fe-80SiC (WL-F5) exhibited similar phase compositions to the TL coating, with no new phase identified in the coatings. However, the TiFeSi₂ and SiC phases were presented in Ti-10Fe-80SiC (WL-F10) and Ti-15Fe-80SiC (WL-F15). It is proven that the addition of the Fe element could regulate the in situ reaction in the original Ti-Si-C ternary system to form the new phases with high hardness and good wear resistance. The hardness of the WL-F15 (1842.9 HV₁) is five times higher than that of the matrix (350 HV₁). Due to the existence of self-lubricating phases such as Ti₅Si₃ and Ti₃SiC₂, a lubricating film was presented in the WL-F0 and WL-F5 coatings, which could block the further damage of the friction pair and enhance the wear resistance. Furthermore, a wear-transition phenomenon was observed in the WL-F10 and WL-F15 coatings, which was similar to the friction behavior of structural ceramics. Under the load of 10 N and 20 N, the wear volume of WL-F15 coating is 5.2% and 63.7% of that in the substrate, and the depth of friction of WL-15 coating is only 14.4% and 80% of that in the substrate. The transition of wear volume and depth can be attributed to the wear mechanism changing from oxidation wear to adhesive wear.

Keywords: TC4 substrate; coating; laser cladding; microstructure; wear behavior.

Grants and funding

This work was supported financially by the National Defense Basic Scientific Research Program of China (Grant No. 2020208B020), the Science and Technology Innovation Program for the High-tech Sector of Hunan Province (Grant No. 2022GK4027), and the Natural Science Foundation of Hunan Province (Grant No. 2020JJ5713).