Microstructure and bubble formation of Al–K–Si doped tungsten prepared by spark plasma sintering. (January 2016)

• Record Type: Journal Article
• Authors: Huang, Bo; He, Bo; Xiao, Ye; Ang, Ran; Yang, Jijun; Liao, Jiali; Yang, Yuanyou; Liu, Ning; Pan, Deng; Tang, Jun
• Is Part Of: International journal of refractory metals & hard materials. Volume 54(2016:Jan.)
• Page Start: 335
• Page End: 341
• Publication Date: 2016-01
• Subjects: Potassium-doped tungsten -- AKS doping -- Spark plasma sintering -- Potassium bubble; 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.2015.08.005
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: Dense potassium-doped tungsten (W–K) ingots with homogeneously dispersed nanoscaled bubbles were fabricated by spark plasma sintering (SPS) using Al–K–Si (AKS) doped tungsten powder. Parameters such as sintering temperature, holding time and sintering pressure were considered to tune the grain size, density, microhardness, bubble formation and impurity contents. In addition, a two-step sintering scheme was designed to reduce Al/Si impurity contents and enhance the density. The sample prepared by the two-step sintering scheme displays both inter- and intra-granular nanocomposites, which is expected to have better creep resistance, high bending strength and fracture toughness. Potassium was detected inside the bubbles, determining the crucial role in the bubble formation process, and thus leading to compatible properties as plasma-facing material. Highlights: Al–K–Si doped tungsten powder was spark plasma sintered. Sintering parameters were tuned according to density, grain/bubble size, etc. A two-step sintering scheme was designed to reduce Al/Si impurity. Potassium was detected inside the bubbles through energy dispersive spectroscopy.