Hearth roll for continuous annealing furnace

A hearth roll for a continuous annealing furnace, the hearth roll comprising a thermal spray coating on a surface of the hearth roll, wherein

• the thermal spray coating comprises main components consisting of a Co-based alloy, a carbide of a transition metal, and a double oxide, and
• impurities,
• the double oxide consists of a first double oxide consisting of Al and a rare earth element, and a second double oxide consisting of a transition metal and a rare earth element,
• a content of the Co-based alloy is 25 mass % or more and 50 mass % or less of the main components, a content of the carbide is 5 mass % or more and 30 mass % or less of the main components, and a content of the double oxide is 20 mass % or more and 45 mass % or less of the main components,
• 2/3≤(A/B)≤4 is satisfied, where A and B respectively denote a molar quantity of the transition metals and a molar quantity of carbon in the carbide, and
• 1≤(C/D)≤4 is satisfied, where C denotes a total molar quantity of Al and transition metals not constituting the carbide in the main components, and D denotes a molar quantity of rare earth element included in the main components.