| 摘要 |
PURPOSE:To improve the flexural strength, thermal shock resistance, hardness, and heat conductivity of the title rolling sleeve and to prolong its service life by using a titanium boride sintered compact to form the sleeve. CONSTITUTION:TiB2 having 0.5-3mum average particle diameter, 6mum maximum particle diameter, and >=99wt.% purity, Ni having 6mum average particle diameter, and carbon having 80-150m2/g surface area, 10-50mum average particle diameter, 100mum maximum particle diameter, and >=99.9wt.% purity are mixed. In this case, the (Ni+C) content is controlled to 2.5-25wt.%, the TiB2 content is adjusted to 75.0-97.5wt.%, and the mixing weight ratio of N/C is controlled to 14/0.2-5. The mixture is compacted and sintered in a non-oxidizing atmosphere at 1600-1800 deg.C to obtain a titanium boride sintered compact wherein a matrix layer of the solid soln. of nicked boride and titanium carbide is arranged between titanium particles and having <=5% porosity. The inner surface of the through-hole is lapped with desired precision to obtain a rolling sleeve. |
