| 摘要 |
PURPOSE:To manufacture a sintered hard alloy material suitable for manufacturing a hot rolling roll, in a sintered hard alloy essentially consisting of WC and contg. Co, Ni and Cr, by specifying the grain size of a hard phase and the content of a bonding phase in the alloy and the content of Cr in the bonding phase. CONSTITUTION:In a sintered hard alloy essentially consisting of WC and contg. Co, Ni and Cr (where the content of WC is regulated to by weight, about 70 to 92%, the weight ratio of Co to Ni in the bonding phase is regulated to about 1:1 to 3.5:1 and the content of Cr is regulated to about 0.5 to 2.0%), the grain size of the hard phase in the alloy is regulated to 4 to 9mm average, the content of the bonding phase is regulated to 8 to 30% in the alloy and the Cr content in the bonding phase is regulated to 0.5 to 2.0%. Because the roll manufactured by using this sintered hard alloy is excellent in thermal characteristics and having improved strength and wear resistance, at the time of providing the surface with a caliber, cracks do not occur. |
