The so-called phenomenon of frost cracking in sesame ash fired boards refers to the situation where, when enough water is absorbed into the fine pores of the board, if the temperature drops below freezing point, the water in the micro gaps of the board will freeze, causing its volume to expand by 1/11. When the expansion force of ice is greater than the bearing capacity of sesame ash fired board, cracks will appear on the board. To prevent the occurrence of ice cracking during sesame ash fire burning, it is necessary to prepare in advance in extremely cold conditions. When extreme cold freezing occurs, resist ice swelling. The following are the methods for dealing with the phenomenon of frost cracking during sesame ash fire burning.

Usually, when the temperature changes, the phenomenon of "thermal expansion and contraction" occurs, and the characteristics of water are exactly different. The water density is high at 4 degrees Celsius, and water molecules will flow independently. When the temperature drops from 4 ℃ to 0 ℃, ice formation occurs, and the water molecules in the ice form a three-dimensional structure, arranged in an abnormal sequence pattern. This layout is prone to leaving many "gaps", and the density will decrease.

Experiments have shown that when 1 cubic meter of water freezes, its volume increases to 1.10 cubic meters. At 0 degrees Celsius, water enters the micropores or gaps of the sesame ash fired board and freezes when it cools, increasing its volume and expanding the micro pores in the board. Then, the sesame ash fired board will absorb more water into the micropores, further expanding the pores and gaps. This cycle repeats, causing cracks in the expansion of the sesame ash fired board.