Study on Hot Corrosion Resistance of In Situ Generated TiC and TiC + TiB Reinforced TB8 Titanium Matrix Composite by Powder Metallurgy

• Published in: Journal of materials engineering and performance 2023, Vol.32 (2), p.835-846
• Main Authors: Li, Shuaidi, Xu, Xiaojing, Luo, Yuntian, Huang, Lin, Wu, Jianming
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Corrosion and Coatings; Engineering Design; Materials Science; Quality Control; Reliability; Safety and Risk; Technical Article; Tribology
• ISSN: 1059-9495; 1544-1024
• DOI: 10.1007/s11665-022-07129-0

TiC and TiC + TiB were prepared through an in-situ reaction and powder metallurgy based on Ti-Mo-Nb-Al-Si matrix powder, CNTs (Carbon Nanotubes) and CNTs + B 4 C, which reinforces TB8 titanium matrix composites (TMCs). Firstly, the hot corrosion performance of three kinds of TiC (0, 2.5, and 5vol.-%) and one TiC + TiB (3.5 + 3.5vol.%) was investigated in Na 2 SO 4 (75wt.%)-NaCl(25 wt.%) saturated solution at 800°C. And then the corrosion kinetics indicated that the corrosion weight gain of 3.5vol.% TiC + 3.5vol.% TiC reinforced titanium matrix composite only reached 7.48 mg/cm 2 . Secondly, the features of corrosion scales formed on the composites were characterized based on x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). The patterns of XRD illustrated the corrosion products are composed of TiO 2 , Al 2 O 3 , SiO 2 , Nb 2 O 5 , TiCl 2 , NaTiO 2 and NaAlO 2 . SEM showed that the corrosion surface of TiC + TiB composite is the densest among the four composite materials (0 vol.% TiC, 2.5 vol.%TiC, 5 vol.%TiC, and 3.5 vol.%TiC + 3.5 vol%TiB). In addition, its corrosion layer thicknesses have little difference, which are 53, 46, 49, and 44  μ m, respectively. Finally, the composite material with TiC + TiB has the best hot corrosion resistance, which verifies by the experimental analysis.