High emissivity coating compositions, and processes for preparing and applying the same

A process for preparing a high emissivity coating composition, comprising steps of

• providing a powder mixture comprising at least three metal compounds of formula A(y−3)By/2Oy, wherein y is 4;
• A is selectable from a group of Ni and Co;
• B is selectable from a group of Fe and Cr;
• and O is oxygen;
• providing a first aqueous solution comprising potassium silicate;
• providing a second aqueous solution comprising
• silica in a compound of Formula (1):
• wherein R1 is H-Si-(CH3)2;
• and
• silica in a compound of Formula (2):
• wherein R2 is CH3;
• and
• mixing the powder mixture with the first aqueous solution and the second aqueous solution.

A process for applying a high emissivity coating composition to a substrate, comprising steps of

• providing a high emissivity coating composition comprising a powder mixture and an aqueous solution;
• spraying the high emissivity coating composition at a surface of the substrate;
• drying the substrate;
• and
• heating the substrate,
• wherein
• the powder mixture comprises at least three metal compounds of formula A(y−3)By/2Oy, wherein y is 4;
• A is selectable from a group of Ni and Co;
• B is selectable from a group of Fe and Cr;
• and O is oxygen;
• and
• the aqueous solution comprises
• silica in a compound of Formula (1):
• wherein R1 is H-Si-(CH3)2;
• and
• silica in a compound of Formula (2):
• wherein R2 is CH3.