How to improve the wear resistance of refractory brick
Refractory bricks are generally made at room temperature and used at high temperature. Therefore, refractory bricks with high wear resistance usually refer to high temperature wear resistance. For the study of wear resistance, we can start with the strength of refractory brick. The improvement of strength will inevitably improve the wear resistance. When used in high-temperature environment, refractory bricks are often washed by high-temperature gas and high-temperature particles. For the parts with serious high-temperature wear of refractory bricks for cement kiln, the wear resistance of refractory bricks is very high.
At this stage, people also put forward some measures to improve wear resistance:
(1) Select materials that meet wear resistance
The wear-resistant mechanism of refractory brick is related to the service temperature. Before the refractory brick produces a liquid phase with high viscosity at low temperature, the wear is mainly reflected in the matrix. At this time, the bonding strength of the matrix determines the wear-resistant performance of refractory brick. When the material produces' liquid phase 'and the viscosity is large, the matrix will produce a certain elasticity when worn. If the particles are brittle at this temperature, the particles will be seriously worn [30]. Therefore, according to the use environment of materials, the reasonable selection of raw materials is of great significance to the wear resistance of refractory bricks.
(2) Reasonable particle size composition
Reasonable particle gradation is the premise of densification of refractory brick. With the same raw materials and preparation process, the denser the refractory brick, the higher the strength, the higher the bonding strength between matrix and between matrix and aggregate, and the stronger the wear resistance of refractory brick. Therefore, the amount of flea in raw materials with different particle sizes has an important impact on the high-temperature wear resistance of refractory bricks.
In addition, the selection of critical particle size also has a great influence on the high temperature wear resistance of castable. Large particles with a certain particle size can produce "negative color effect" when the matrix is worn, so as to reduce the wear of the matrix and improve the wear resistance of refractory bricks. Therefore, reasonably increasing the critical particle size of refractory brick raw materials can also improve the wear resistance of refractory bricks to a certain extent.
(3) Improve the strength of refractory bricks
The wear resistance of wear-resistant refractory brick is directly related to its strength. The higher the strength at high temperature, the higher the bonding strength between the matrix and aggregate of refractory brick. If there are too many defects and cracks in the microstructure at high temperature, the material strength will be reduced, and the wear will be increased accordingly. Therefore, how to improve the strength of castable at high temperature is one of the important ways to solve the high temperature wear resistance.