Hearth roll for continuous annealing furnaces, and method for manufacturing same
AssigneeNippon Steel & Sumikin Hardfacing Co., Ltd.
InventorsYasushi Kurisu, Yu Li
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Abstract
A hearth roll for heat treatment furnaces has excellent build-up resistance, has a hexavalent-chromium-free thermal spray coating film formed on the roll surface thereof and is safe for the environment. A method for manufacturing a hearth roll for continuous annealing furnaces includes a first step of applying an aqueous solution containing chromium phosphate onto a thermal spray coating film formed on the roll surface of a hearth roll or impregnating the thermal spray coating film with the aqueous solution; and a second step of burning the hearth roll.
Claims5
A method for manufacturing a hearth roll for continuous annealing furnaces, comprising:
- a first step of applying an aqueous solution containing chromium phosphate onto a thermal spray coating film formed on a roll surface of the hearth roll;
- and
- a second step of burning the hearth roll,
- wherein the thermal spray coating film is a CoCrAlY-based cermet thermal spray coating film, and
- when an amount of the aqueous solution is 100% by mass, a concentration of chromium phosphate is 5% by mass to 30% by mass, and a concentration of chromium in the chromium phosphate is 1.5% by mass to 15% by mass.
Dependencies are inferred from the claim text.