Patent ID: 6180182
Filing Date: 2001-01-30
Classification: C04B,C25C,Y10T

Abstract:
A method for producing an improved carbon body to be used as cathode block in cells for the electrowinning of aluminum, to which a hard surface is provided by applying to the surface of the carbon body one or more layers containing particulate refractory hard metal boride and a carbon-free bonding material which when the carbon body is heated reacts with the refractory hard metal boride and carbon from the surface of the carbon body or from a carbon-containing atmosphere, comprising applying to the carbon body one or more layers of particulate refractory hard metal boride with the bonding material, and heating the body under a non-oxidizing atmosphere to cause the bonding material to react with the refractory hard metal boride and carbon from the carbon-containing body or from a carbon-containing atmosphere, to form the hard surface layer.