Sub-micron binderless tungsten carbide sintering behavior under high pressure and high temperature. (January 2016)

• Record Type: Journal Article
• Authors: Ma, Dejiang; Kou, Zili; Liu, Yinjuan; Wang, Yongkun; Gao, Shangpan; Luo, Xi; Li, Wentao; Wang, Yonghua; Du, Yanchun; Lei, Li
• Is Part Of: International journal of refractory metals & hard materials. Volume 54(2016:Jan.)
• Page Start: 427
• Page End: 432
• Publication Date: 2016-01
• Subjects: High pressure -- High temperature -- Tungsten carbide -- Grain growth -- Stacking fault; 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.2015.10.001
• Languages: English
• ISSNs: 0263-4368

Abstract

Abstract: Pure tungsten carbide (WC) compacts of about 200 nm grain size were prepared by high pressure and high temperature (HPHT) method. The best property sample with high relative density (99.2%), high Vickers hardness (2925 kg·mm − 2 ) and high fracture toughness (8.9 MPa·m 1/2 ) was obtained in the condition of 1500 °C temperature and 5 GPa pressure. By means of scanning electron microscopy (SEM) and transmission electron microscope (TEM) observations, a large number of twins and stacking faults appeared in sintered samples, and the grain size of sintered samples maintained in the initial range. The XRD patterns of bulk samples reveal that there is a phase transition from WC to W2 C with the increasing of temperature. Moreover, the effect of HPHT condition for sintering kinetics, microstructure evolutions, and mechanical properties of the sintered samples were also discussed. Highlights: The pure tungsten carbide compacts were sintered by high pressure and high temperature (HPHT) method. The twins and stacking faults appeared extensively in the sintered samples. The hardness tests give an average Vickers hardness of 29 GPa for the well-sintered WC. The grain sizes of the sintered samples maintained in the initio range.