| 摘要 |
PROBLEM TO BE SOLVED: To provide a cemented carbide that has smaller bias of particle size distribution of hard phase particles as compared with that of the conventional ones and is excellent in abrasion resistance and defect resistance.SOLUTION: The cemented carbide is formed by binding a hard phase mainly composed of WC particles with a binder phase mainly composed of Co. An average particle size of WC particles constituting the hard phase of the cemented carbide is less than 0.4 μm and a degree of dispersion as an index showing uniformity of the WC particle size is 0.55 or less, preferably, 0.50 or less. [the degree of dispersion is a value obtained by dividing the half value width (circle equivalent diameter when the cumulative frequency is 75%-circle equivalent diameter when the cumulative frequency is 25%) by the average particle size (50% particle size) of the WC particles]. An average circularity of the WC particles is 0.68 or more, preferably, 0.75 or more. The cemented carbide has more excellent abrasion resistance and defect resistance than those of the conventional ones and consequently, and thereby can be suitably used for various working tools. |
