Insights into microstructural evolution and dissolution characteristics of reinforced particles in tungsten carbide‑nickel composite coatings prepared by laser hot-wire deposition. (February 2022)

• Record Type: Journal Article
• Authors: Zhao, Shengbin; Jia, Chenpeng; Yuan, Yuxue; Wang, Lixin; Huang, Yiming; Yang, Lijun
• Is Part Of: International journal of refractory metals & hard materials. Volume 103(2022)
• Publication Date: 2022-02
• Subjects: Dissolution characteristics -- Microstructural evolution -- Tungsten carbide -- Composite coating; 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.2021.105720
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: Tungsten carbide‑nickel (WC-Ni) composite coatings were firstly prepared on martensite stainless steel 2Cr13 by laser hot-wire deposition. The microstructural evolution and the dissolution characteristics of ceramic particles in the coatings had been systematically investigated. The results showed that the tungsten carbides' dissolution and microstructures in the coatings were close related to the dilution degree of the base metal. Apart form large retained particles, the coating with a lower dilution ratio (8.4%) was composed of Ni, Ni/Ni3 B eutectics, and in-situ W2 C particles. The W2 C phase was preferentially dissolved while the WC was retained in W2 C/WC eutectoid-structured particles, which exhibited the typical thermal damage patterns including the dissolution-diffusion and partially/completely fragmentation-dissolution-diffusion. The amount of M6 C carbides was increased with the increment of dilution ratio (from 9.5% to 24%), and the ceramic particles suffered from more severe heat damage which mainly exhibited the characteristics of dissolution-diffusion-precipitation. Not only was the W2 C phase was dissolved, the WC phase was also decomposed and reacted into M6 C carbides. Due to the reinforcement of retained particles and the precipitated carbides, these coatings showed higher hardness and wear resistance which was about 1.9– 2.3 and 12.1– 26.9 times that of 2Cr13 substrate. Highlights: Characteristics of reinforced particle's dissolution was depended on dilution ratio of substrate. Five different kinds of thermal damage patterns of ceramic particles were analyzed. Microstructural evolution of the coatings was closely related to the dilution ratio of substrate. Formation mechanisms of the W-rich carbides were investigated comprehensively.