【摘要】 本文在Wagner理论和固体电子理论的基础上,将电导率与电子的平均自由程及晶粒尺寸的关系联系起来,建立了纳米及超细晶结构金属腐蚀速率—晶粒尺寸关系模型,并结合锆金属的性质,模拟计算了不同温度下晶粒尺寸对锆合金腐蚀速率常数的影响,结果表明,与普通晶粒相比,纳米晶粒尺寸下锆Zr的腐蚀速率常数和腐蚀增重,远低于普通晶粒纯Zr的腐蚀速率常数和腐蚀增重,同时,随着纳米晶粒尺寸的减小Zr的腐蚀速率常数也降低,显示晶粒纳米化处理可以改善锆金属的腐蚀性能。更多还原

【Abstract】 In this paper a computation model of corrosion rate-grain size of nanocrystalline and ultra-fine zirconium has been presented.The model is based on the Wagner’s theory and the electron theory of solids.The conductivity,electronic mean free path and grain size of metal were considered.By this model,the corrosion rate of zirconium metal under different temperature was computed.The results show that the corrosion weight gain and rate constant of nanocrystalline zirconium is lower than that of zirconium with coarse grain size.And the corrosion rate constant and weight gain of nanocrystalline zirconium metal decrease with the decrease of grain size.So the refinement of grain size can remarkably improve the corrosion resistance of zirconium metal.更多还原