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经对包括 Zr- 4在内的 4种不同成分锆合金耐腐蚀性能的研究发现：高温水中添加了 0.01～ 0.1molLiOH后，腐蚀转折提早发生，转折后的腐蚀速率增加。这种现象随 LiOH浓度增大变得更加显著，但在成分不同的锆合金中有明显的差异，同时添加 H3BO3后又可以抑制 LiOH的加速腐蚀作用。氧化膜显微组织的观察结果表明：转折后的加速腐蚀过程与氧化膜中孔洞簇的出现有关，添加 LiOH以及改变合金成分后，通过影响孔洞簇的形成而对腐蚀转折及转折后的腐蚀加速产生作用。从分析氧化膜中 Li＋的浓度及有关腐蚀增重的结果来看，似乎 Nb可以部分抑制 Li＋进入氧化膜，而足够含量的 Sn可以缓解 Li＋的有害作用。因此，只有 Sn和 Nb含量都比较高的 3样品，在含 LiOH介质中的耐腐蚀性能最好，而含 Sn和 Nb较低的锆合金样品，在这种条件下的耐腐蚀性能还不如 Zr- 4。这些锆合金在不含 LiOH的 400℃过热蒸汽中腐蚀时，表现出耐腐蚀性能的变化规律，与含 LiOH高温水中的正好相反，说明了这两种条件下影响腐蚀性能的主导因素有着明显的不同。在靠近氧化膜 /金属界面处的氧化膜，无论在转折前或转折后，都存在亚稳的非晶、立方和四方结构的 ZrO2，没有观察到孔洞，在氧化膜中间层和表层已生成孔洞处，是单一的单斜结构 ZrO2，
The corrosion resistance of four different zirconium alloys, including Zr-4, was studied. The results show that corrosion resistance increases early after the addition of 0.01 ~ 0.1 mol LiOH in high temperature water. This phenomenon becomes more significant with the increase of LiOH concentration, but there are obvious differences in the zirconium alloys with different compositions. At the same time, the addition of H3BO3 can inhibit the accelerated corrosion of LiOH. The results of the microstructure of the oxide film indicate that the accelerated corrosion process after the break is related to the appearance of the hole clusters in the oxide film. After the addition of LiOH and the alloy composition, the corrosion transitions and the corrosion after the break are accelerated by affecting the formation of the hole clusters Have an effect. From the analysis of the concentration of Li + in the oxide film and the results on the corrosion weight gain, it seems that Nb can partially suppress the entry of Li + into the oxide film, while sufficient Sn content can alleviate the detrimental effects of Li +. Therefore, only the 3 * samples with relatively high Sn and Nb contents show the best corrosion resistance in the LiOH-containing medium, while the samples with lower Sn and Nb zirconium alloys show less corrosion resistance under these conditions Zr-4. These zirconium alloys showed no change in corrosion resistance when they were subjected to superheated steam at 400 ° C without LiOH, which was the opposite of that in LiOH-containing high-temperature water, indicating that the dominant factors affecting the corrosion performance in these two conditions are obvious different. In the oxide film close to the oxide film / metal interface, metastable amorphous, cubic and tetragonal ZrO2 existed before or after the transition, no voids were observed, and voids were formed in the oxide film intermediate layer and the surface layer Department, is a single monoclinic structure ZrO2,