Y_4Si_2O_7N_(2-)BN复合材料抗热震性能研究

Thermal Shock Resistance of Y_4Si_2O_7N_(2-)BN Composites

系统地研究了Y4Si2O7N2-BN复合材料的抗热震性能.计算表明,Y4Si2O7N2-30vol.%BN复合材料具有较高的热应力断裂抵抗因子R1值.进一步的实验证明该复合材料的临界热震温差为850~900 K.第二相h-BN在热震条件下的层间劈裂愈合机制对复合材料保持较高的残余强度有利.

The thermal shock resistance of Y4Si2O7N2-BN composites has been systematically studied in this paper.The thermal stress fracture resistance parameter,R1 of Y4Si2O7N2-30vol.%BN composite is higher than that of Y4Si2O7N2 and Y4Si2O7N2-20vol.%BN composite.Then the critical temperature difference（ΔTc） of Y4Si2O7N2-30vol.%BN composite is determined to be 850~900 K.The excellent thermal shock resistance is attributed to the lamination structure of h-BN grain which could dissipate the energy by healing up during heating and delamination during cooling.