| 摘要 |
PURPOSE:To provide the titled metal needle having excellent fatigue strength and high reliability, by providing a WC-Co super hard alloy needle in which Co content is in a specified range and average particle diameter of WC is not larger than a specified value. CONSTITUTION:When a super hard alloy needle having a Co content of 20-30wt% and an average particle diameter of WC not larger than 1.2mum was fitted into a printer and a printing test was conducted, the needle can be used at least one billion (1X10<9>) times in printing dots without breakage. The titled needle with high fatigue strength, and high reliability against breakage can be obtained when the needle is used in a dot-type printer. |
