冷等静压成型压力对反应烧结氮化硅陶瓷性能的影响

将硅粉冷等静压成型,通过反应烧结得到氮化硅陶瓷,研究了成型压力对反应烧结氮化硅(RBSN)陶瓷性能的影响。结果表明,当成型压力从100MPa增加到300MPa,反应烧结氮化增重率逐渐下降,从60.25%降到47.31%;而残余硅含量随着增加,从10%增加到29%;RBSN开气孔率随着成型压力的增大而减小,开气孔率从20.50%降到13.81%。成型压力小于等于200MPa时,RBSN的密度和强度随成型压力的增大而增大;成型压力大于200MPa时,RBSN的密度随成型压力的增大而减小,强度随成型压力的增大变化不大,变化约为5%;在200MPa时,RBSN的密度达到最大值2.52 g/cm3。冷等静压成型RBSN由晶须状α-Si3N4,柱状β-Si3N4和残余硅组成。

Pressure Effect of Cold Isostatic Pressing on Performance of RBSN

The silicon green compacts have been formed by the cold isostatic pressing.The Si3N4 was sintered by reaction sintering process.The effects of forming pressure on the performance of RBSN were studied.The weight gain percent of the reaction sintering was gradually decreased from 60.25% to 47.31%,the silicon residue was increased from 10% to 29%,and the open porosity of the RBSN was decreased from 20.50% to 13.81%,when the molding pressure was increased from 100MPa to 300MPa.The density and strength of the RBSN were increased with the forming pressure increasing when the forming pressure was less than or equal to 200MPa.With the forming pressure increasing,the density of RBSN was decreased,and the effect on the strength was little and the change was only about 5%,when the forming pressure was greater than 200MPa.The density of RBSN reached a maximum of 2.52 g/cm3 at 200MPa.The RBSN was composed of whisker-like α-Si3N4,columnar β-Si3N4,and silicon residue.