Fabrication And Thermal Resistance Of Al₂TiO₅/MgTi₂O₅ System Composites

Aluminium Titanate (Al2TiO5,AT) has many excellent properties such as low thermal expansion coefficient, thermal conduction coefficient, high melting point, endured corrosion and thermal resistance, so it is one of the best materials with low thermal expansion coefficient resisting high temperature. For the sake of overcoming the two fatal disadvantages of AT that its density and strength is low,and in the middle temperature range it can decompose into AhOs and TiC>2 easily.In this dissertation, Magnesium dititanate(MgTi2Os,M2T)is introduced to form solid solution to restrain the decomposition and improve the strength of AT in high temperature. The thermal resistance, synthesize fabrication and structure character are emphasized.The experimental results show thatthe high sintered density of M2T and fine thermal stability could got with the 5wt% additive of ZrO2 at 1500C for 2 hours .and the additive of M2T can effectively restrain the decomposition of AT and promote the sinter process, which enhanced the density of AT and promote the strength. Study of the thermal resistance of AT/M2T composite show that the thermal resistance of composite with 30mol%M2T is reformed in evidence .When the content of M2T is 40vol%, the AT/M2T composite possess the best thermal resistance properties ,which is kept at 700 C for 64 times.and its surface is still fine.