【摘要】 热压氮化硅陶瓷在急冷法热疲劳条件下,其力学性能(强度、断裂韧性)都发生了较大幅度的下降。由于温度对裂纹生长的促进作用,在相同热疲劳条件下,材料高温性能损伤大于常温性能损伤。由于表面热疲劳裂纹的产生,使得材料强度性能损伤大于断裂韧性损伤。在涡流状空气热疲劳条件下,热压氮化硅的高温强度也发生了下降,但下降程度远小于急冷法中的性能下降。更多还原

【Abstract】 Under rapid quenching conditions,the mechanical properties(strength,fracturetoughness)of HPSN ceramics decreased rapidly.Because of the promotion of tempe-rature to cracks,the high temperature property loss of HPSN is much greater thanthe room temperature property loss,although they are in the same thermal fatigueconditions.The strength loss is greaser than the fracture toughness loss,because ofthe surface cracks caused.by thermal fatigue.Under turbulent air thermal fatigue,the high temperature strength of HPSN alsodecreased,but the decreasing extent in turbulent air is much smaller than that underrapid quenching conditions.更多还原