Phosphate coating resistant to 1,800 degrees celsius for heat insulation and fireproofing and preparation method thereof

A phosphate coating composition resistant to 1,800 degrees Celsius for heat insulation and fireproofing, comprising:

• 20-30 parts by mass of aluminum dihydrogen phosphate, 10-20 parts by mass of zinc oxide, 10-20 parts by mass of cerium oxide, 5-15 parts by mass of gadolinium zirconate, 5-15 parts by mass of polysiloxane, 3-10 parts by mass of zirconium boride, 3-10 parts by mass of hafnium carbide, 3-5 parts by mass of zirconium powder, 3-5 parts by mass of tungsten powder, 10-15 parts by mass of fibers, 3-10 parts by mass of chromium trioxide, 3-10 parts by mass of potassium chromate, 0.4-1 part by mass of non-silicone defoamer, and 5-15 parts by mass of deionized water;
• wherein the phosphate coating composition is prepared by a process comprising the following steps:
• step 1, weighing 20-30 parts by mass of the aluminum dihydrogen phosphate, 10-20 parts by mass of the zinc oxide, 10-20 parts by mass of the cerium oxide, 5-15 parts by mass of the gadolinium zirconate, 5-15 parts by mass of the polysiloxane, 3-10 parts by mass of the zirconium boride, 3-10 parts by mass of the hafnium carbide, 3-5 parts by mass of the zirconium powder, 3-5 parts by mass of the tungsten powder, 10-15 parts by mass of the fibers, 3-10 parts by mass of the chromium trioxide, 3-10 parts by mass of the potassium chromate, 0.4-1 part by mass of the non-silicone defoamer, and 5-15 parts by mass of the deionized water;
• step 2, ball milling the aluminum dihydrogen phosphate, the zinc oxide, the cerium oxide, the gadolinium zirconate, the polysiloxane, the zirconium boride, the hafnium carbide, the zirconium powder, the tungsten powder, the chromium trioxide and the potassium chromate with a ball mill in a ball mill using anhydrous ethanol as a medium, followed by drying and sieving to obtain a sieved powder;
• wherein the ball milling in step 2 is performed for a duration of 500-1,200 minutes at a rotating speed of 300 to 600 revolutions per minute;
• the sieving in step 2 comprises sieving powders through a 300-500 mesh sieve;
• and
• step 3, adding the sieved powder and the fibers into the deionized water, and stirring the resulting mixture under water-bath heating conditions, followed by adding the non-silicone defoamer, and stirring and heating the resulting mixture to a gel state to obtain the phosphate coating composition;
• wherein a temperature for the water bath in step 3 is 85-95 degrees Celsius, and the stirring in step 3 is performed at a stirring speed of 450 to 750 revolutions per minute.