The Hollow Cathode Discharge Plasma Sintering Of Aluminium Nitride Ceramic

By using the technology of Hollow Cathode Discharge Plasma(HCDP),A1N ceramics with high performances of high density and excellent conductivity was produced with the A1N powder as raw materials which are produced by the method of SHS and the Y₂O₃-CaO-Li₂O as the additives in this paper．Through studying the characteristic of columnar Hollow Cathode Discharge,wedetermined to use the Hollow Cathode Discharge technology to sinter A1N Ceramic,the feasibilities and advantages of applying Hollow Cathode Discharge to sintering ofCeramic are pointed out．Effective additives are selected after thermodynamics analysis and the Hollow Cathode Discharge sintering experiments,the mechanism of its promoting sintering capability are indicated,the affect of different technical parameters towards the performances of AIN Ceramic are explored The results of study show that Hollow Cathode Discharge Plasma is effective sintering method in sintering of A1N ceramic and Y2O3-CaO-Li2O are effective additive system to promote the densification process of A1N sintered at low temperature．In this paper,the additive system of Y2O3-CaO-Li2O was systemic investigated,the relation of densities between the amount of additives,sintering temperature and holding time were studied,the best technical parameters are obtained The results show:The densities of samples sintered at temperature of 1700℃ reached the highest relative density of 98．88ï¼…after holding 3h,the amount of sintering additives is 5．5 wtï¼…(wtY2o3:WtLi20:wt cao:=44:6:5),thermal conductivity is 93．8 W／(m．K)．The SEM show that the A1N grains grow perfectly and have clear, sharp．edge and multilateral morphology,grain boundary phase and pores are little and homogenously distributed,A1N phase is contiguous and the form of rupture is through grain．TEM show that boundary phase is little and consist in triangle grain boundary.