The Effect Of Carbon Powder On The Synthesis And Sintering Properties Of AlON Powder

Spinel-type alumina is an isotropic polycrystalline ceramic material with excellent optical and mechanical properties comparable to sapphire single crystal,which can be applied to transparent armor,infrared window materials and fairing.In this paper,the name ofγ-Al₂O₃and four different carbons with different surface areas,using a two-step carbon thermal reduction nitride method to prepare high purity AlON powder at 0.03 wt.%and so on Y₂O₃ for sintering additives,the traditional pressureless sintering was used to prepare AlON transparent ceramics.Nitriding by carbon thermal reduction prepared AlON powder,The Al₂O₃/C ratio is extremely difficult to control and difficult to mix evenly.In view of the above problems,this paper selects AlON powder of different surface areas,clarifies the role of toner of different surface areas in preparing AlON powder by carbon thermal reduction and nitride,and determines the toner raw materials needed for this topic.On this basis,AlON powder with different carbon parameters was prepared,clarifying the influence of toner content on the preparation of AlON powder by carbon thermal reduction,and determining the best carbon parameters.And these AlON powders were prepared into AlON ceramics.The specific results are as followsThe AlON powder prepared by the VXC72 model toner has a good purity and uniform and fine particle size distribution.The generation and growth of the AlON phase in carbon thermal reduction nitride occurs in toner-coated Al₂O₃ particle surface,thus resulting in a AlON micromorphology with Al₂O₃has a large correlation.The AlON lattice constant does not change with the toner characteristics.AlON powder preparation technique of heating up to 1550℃for1h at 5℃/min and then to 1750℃for 5h was determined.The AlON lattice constant also increases with the carbon parameter,the larger the carbon parameter,the greater the amount of Al N phase in AlON powder,and the bond length of Al N phase is longer than Al₂O₃.The bond length of the phase causes the gradual increase of the lattice constant of the AlON powder.The carbon parameter of 5.6%can produce AlON powder with uniform particle size distribution and high purity.The different carbon parameters had no effect on the particle size distribution of the corresponding prepared AlON powder.The more sectional cracks of AlON ceramics prepared by AlON powder with the higher the carbon parameter,the smaller the ceramic grains.This is mainly because the content of Al N in AlON powder with more carbon parameters is higher and the strength of chemical bonds in Al N is higher,thus limiting the growth of AlON ceramic grains.The AlON ceramic preparation technique was determined by increasing the temperature at 5℃/min and then increasing the temperature at 5℃/min to 1930℃for 5 hours.