Enamel ground coat and preparation method

An enamel ground coat is prepared from the following raw materials in parts by weight: 42-60 parts of waste rare earth polishing powder, 15-25 parts of aluminum oxide, 5-15 parts of boron oxide, 1-3 parts of potassium oxide, 8-12 parts of sodium oxide, 2-8 parts of calcium fluoride, 1-2 parts of nickel oxide and 1-2 parts of manganese oxide. The preparation method of the enamel ground coat comprises the following steps: 1) mixing 20-40% of waste rare earth polishing powder in the raw materials with other materials, and stirring for 5-10 minutes to obtain a first mixture; 2) mixing the first mixture with the remaining waste rare earth polishing powder, and stirring for 10-20 minutes to obtain a second mixture; 3) putting the second mixture into a smelting furnace for roasting at the roasting temperature of 400-1300 DEG C for 2-4 hours to obtain a melt; and 4) carrying out rapid water quenching treatment on the melt, and drying to obtain a finished product. After being applied, the enamel ground coat is good in