A systematic study of the effect of calcium on the production and properties of WC precursor powders and alloys
| Autor: | Hai Kuang, Wen He, Zhihang Zou, Xin Yang, Dunqiang Tan, Wang Xiaoru |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
Scanning electron microscope 020502 materials Metallurgy chemistry.chemical_element Sintering 02 engineering and technology Tungsten 021001 nanoscience & nanotechnology Carbide chemistry.chemical_compound 0205 materials engineering chemistry Flexural strength Tungsten carbide Transmission electron microscopy Cemented carbide 0210 nano-technology |
| Zdroj: | International Journal of Refractory Metals and Hard Materials. 74:61-69 |
| ISSN: | 0263-4368 |
| DOI: | 10.1016/j.ijrmhm.2018.03.002 |
| Popis: | Effect of calcium on tungsten oxide, tungsten, tungsten carbide and WC-Co cemented carbides, and the evolution of Ca during the preparation of cemented carbides were investigated studied by the liquid-solid doping method. X-ray diffraction, scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions, particle sizes and morphologies of them, respectively. The results showed that 1% Ca-doped tungsten oxide consisted of WO3 and CaWO4 phases. After hydrogen reduction, the size of Ca-doped tungsten decreased slightly. During carbonization, most of the CaWO4 and Ca4.26W10O30 transformed to CaC2. After that, the majority rest of the CaWO4 and Ca4.26W10O30 both reduced to CaO in the sintering process. The microhardness, flexural strength and fracture toughness of 1%Ca-doped WC-6wt.%Co cemented carbide were 14.83 GPa, 1456 MPa and 9.98 MPa m1/2, decrement of 10.12%, 29.53%, and 10.57%, respectively. A refining mechanism for tungsten and a weakening mechanism for WC-Co cemented carbides were proposed. |
| Databáze: | OpenAIRE |
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