Deposition and oxidation behavior of Mo(Si, Al)2/MoB layered coatings on TZM alloy. (September 2017)

• Record Type: Journal Article
• Authors: Zhang, Ping; Guo, Xiping; Zhang, Chunying; Tao, Qing; Shen, Chengjin
• Is Part Of: International journal of refractory metals & hard materials. Volume 67(2017)
• Page Start: 32
• Page End: 39
• Publication Date: 2017-09
• Subjects: Mo based alloy -- Mo(Si, Al)2/MoB layered coatings -- Two-step pack cementation -- Oxidation; Heat resistant alloys -- Periodicals; Refractory materials -- Periodicals; Metallography -- Periodicals; Alliages réfractaires -- Périodiques; Matériaux réfractaires -- Périodiques; Métallographie -- Périodiques; Heat resistant alloys; Metallography; Refractory materials; Periodicals; Electronic journals; 669.73
• DOI: 10.1016/j.ijrmhm.2017.04.008
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: A two-step pack cementation process including first boronizing and then co-depositing of Si-Al-Y with different Al contents (0, 5 and 10 wt%) in the packs was used to deposit oxidation-resistant coatings on TZM alloy. The as-formed coatings are MoSi2 /MoB, Mo(Si, Al)2 /MoB, and Mo(Si, Al)2 /Mo-Al-B/MoB layered coatings respectively. Compared with the MoSi2 /MoB coating, the improved oxidation-resistant performance is presented in the Mo(Si, Al)2 /MoB and Mo(Si, Al)2 /Mo-Al-B/MoB coatings upon oxidation at 1250 °C, which should be attributed to the sluggish inward diffusion of Si into substrate and forming dense scales composed of SiO2 and Al2 O3 . The microstructure change and oxidation behavior of these coatings are investigated. Highlights: Mo(Si, Al)2 /MoB layered coatings were prepared on TZM alloy. Microstructures of the coatings containing different Al contents were studied. The Al content in the coatings imposed a significant influence on their oxidation. A sluggish inward diffusion of Si into substrate is observed in the coatings.