Study On Preparation Process Of Silicon Oxide Ceramic Core For Investment Casting Hollow Blade

The study of the preparation process of silicon ceramic core for hollow blade with complex structure and different thickness by using silicon oxide as base material is carried out.The influence of slurry temperature,injection time,injection pressure,initial heating rate and final heating temperature on rate of finished core ceramic is studied in detail by means of experiments.Finally,the ceramic core was prepared to meet the needs of the casting process of the turbine blade,and the casting qualification rate of the blade was improved.The results of the study are of high application value and engineering significance.When the temperature of the slurry is 95℃,with the increase of the injection time,the product of the wet core is first increased and then decreased.With the increase of injection pressure,the rate of the wet core product first increased to the maximum and then decreased or maintained.When the injection time is 12 s and 15 s,and the injection pressure is 5.5MPa,the maximum rate of wet core only reach 65%.When the temperature of the slurry is 100℃,the maximum rate of wet core can reach 95% when the injection time is 9s-12 s and the injection pressure is 5.5MPa.When the slurry temperature is 105℃,the rate of finished product has the maximum value of 100% in the range of 4.5MPa-6.5MPa.When the temperature of the slurry is 110℃,the injection pressure of 5.5MPa is suitable for the injection time of 6S to9 s.When the temperature of the slurry is 115℃,the injection pressure should be in the range of 5.0-5.5MPa.The rate of wet core increased with the increase of slurry temperature.After slurry temperature reaching 105 C,the maximum rate was maintained at 100%,and the number of process parameters that exceed 85% and100% of the finished wet core is most.The sintering scheme optimization is the process scheme of initial heating rate of 100℃/h and the final sintering temperature of 1165 ℃.The main parameters:200 ℃ insulation(heating for 1 hours,keeping for 4 hours),400 ℃ insulation(heating for 2 hours,keeping for 4 hours),600 ℃ insulation(heating 1 hours,keeping for 2 hours),900 ℃ insulation(heating for 1 hour,keeping for 1 hour),1165℃ insulation(heating for 1.5 hours,keeping for 4 hours).