Data Analysis For Thermal Expansion Behavior Of Magnesium Matrix Composites

It is widely used in iron and steel, cement, glass and other high temperature industries for its excellent mechanical properties at high temperature, thermal properties and high corrosion resistance of magnesium-based composite material,widely used. However, compared with the traditional refractories, the unfavorable factor of high thermal expansion characteristics of magnesium-based composite material increases the uncertainties of production and use of magnesium-based composite material. In order to study systematically the basic theory of unburned magnesium-based composite material on the process of production and use, the thermal expansion equipments are used to detect the thermal expansion values in the heating process at different temperatures. The effect of thermal expansion on sintering property and thermal shock resistance of unburned magnesium-based composite material was studied. The using condition was simulated at experiment. The results showed that the liner expansion rate of magnesium-based composite material increased obviously at 1100℃ ~ 1300℃. The increasing trend of liner expansion at1100℃ ~ 1300℃ can be gradually weaken by adding zirconia. The liner change,apparent porosity of magnesium- based composite material after burning at 1100℃and 1500℃ increases with the increase of zirconium dioxide addition. The starting temperature of in situ spinel reaction in the magnesium-based composite material can be reduced by titanium dioxide introduction, and the sintering property and thermal shock resistance can be promoted. The inflection point of the liner expansion coefficient and liner expansion rate occurred at 1170℃ when zircon was introduced in magnesium-based composite material, and the maximum of liner expansion coefficient occurred at 1300℃. The bulk density and the flexural strength of magnesium matrix momposites burned at 1500℃ increased with zircon increases when the amount of zircon addition is less than 6%. The linear expansion coefficient of magnesium matrix composite reached maximum value at about 1300℃ when the aluminum slag was introduced. The sintering property of magnesium matrix composites was promoted by aluminum slag addition. Thermal shock resistance of magnesium matrix composite burned at 1500℃ would be best when 2% aluminum slag was added.