【摘要】 文章描述PWR失水事故工况下燃料包壳与水蒸汽的氧化反应行为。国产Zr-4包壳管在900-1500℃流动水蒸汽中的等温反应速率在1000℃以上遵循抛物线规律,ZrO₂层、α-Zr（O）层和ZrO₂+α-Zr（O）层的成长在此温度以上也遵循抛物线规律,其速率常数分别为:K,（O₂）=4.98 ×10⁵exp（-20907/T）,mg²·cm⁴·s^-1;K,（ZrO₂）=0.0104exp（-17592/T）,cm²·s^-1;K,（α-Zr（O））=0.6407exp（-23207/T）,cm²·s^-1;K,（ξ）=0.3025exp（-20194/T）,cm²·s^-1。高温水中形成的氧化膜使1100℃以下的锆合金与水蒸汽的反应速率降低,不同表面处理和热处理对其影响极小。Zr-2和Zr-4在高温水中的氧化速率无明显差异,Zr-2.5Nb抗高温水蒸汽的氧化能力优于Zr-2和Zr-4。Zr-4合金在高温水蒸汽中的氧化增重超过35mg·cm^-2时,氧化膜易出现剥落和破裂。更多还原

【Abstract】 The isothermal reaction rate of domestic Zircaloy--4 in flowing steam is measured in the temperaurerange of 900--1500℃. The reaction rate measured from the weight gain of the sample follows theparabolic law above 1000℃, the growth rates of ZrO₂ layer, oxygen--stablized alpha phase α--Zr （O）layer and ZrO₂ + α--Zr （O）layer are also parabolic above 1000℃. The parabolic rate constants are K_p（O₂） = 4.98×10⁵exp（--20907/ T ）, mg²·cm^-4·s^-1; K_p （ZrO₂） = 0. 0104 exp（--17592/ T ）,cm²·s^-1; K_p（α--Zr （O） ） = 0.6407exp（--23207/ T ）,cm²·s^-1; K_p（ξ） = 0. 3025exp（--20194/ T）, cm²·s^-1. The oxide film produced in high temperature water decreases Zircaloy--steam reaction ratesat 1100℃ or less. Different surface treatments（pickling and polishing）and different heat treatments （αannealing and β quenching） have small or neglible effects. Oxidation rates of Zircaloy--2 and Zircaloy--4in high temperature steam haven’t distinct difference, but the high tempetature steam oxidation resis-tance of Zr--2.5Nb is superior to that of Zircaloy--4 and Zircaloy--2. It is found that when the oxideweight gain of Zircaloy--4 in high tempetature steam in larger than 35mg·cm^-2, the oxide film easilyseperates and spalls.更多还原