セラミックスの熱衝撃試験における臨界急冷温度差に及ぼす物性値の温度依存性の影響

抄録

The critical temperature difference Δθ_c was determined by the water quenching test for two differently sized ceramic specimens to study the effects of temperature dependence of material properties and heat transfer coefficient on the thermal shock resistance of ceramics. The observed Δθ_c at each Biot number β were compared with those calculated numerically, considering the temperature dependence of material properties and heat transfer coefficient h in the thermal conduction equation. The Δθ_c changed with the size of the specimen, but the thermal shock fracture resistance R was constant for the same type ceramics. Therefore, it was suggested that the R was independent of β and useful for the evaluation of thermal shock resistance.