锆合金疖状腐蚀研究综述

疖状腐蚀是沸水堆中锆合金表面经常发生的1种局部腐蚀现象，它的产生直接影响包壳管的使用寿命和反应堆的安全性，为了全面认识疖状腐蚀的发生、发展及其控制因素，本文总结了国内外疖状腐蚀研究方面的一些主要成果，介绍了疖状蚀斑的形貌、形成机理以及及影响因素。在形成机制方面，目前主要有KUWAE的氢积聚模型和周邦新的形核长大模型。在疗状腐蚀的影响因素方面，认为主要有表面影响、热处理影响、合金成分影响、第二组影响、辐照影响等。最后指出了提高材料抗疗状腐蚀性能的工艺措施：提高Fe Cr含量、降低Sn含量、昼减少淬火后的退火次数和退火温度、降低锆合金制品的表面粗糙可以有效提高锆合金的抗疖状腐蚀能力，最根本的措施还是使用含铌新锆合金。

Nodular Corrosion of Zirconium Alloys

Nodular corrosion a local corrosion occurring on the surface of zirconium alloys usually in boiling water reactors (BWR), directly affects service life of the zirconium cladding and threatens the safety of reactors. The occurrence, propagation morphology of nodules and other characteristics of nodular corrosion, are summarized. The commonly accepted models of nodular corrosion include the hydrogen accumulation model of KUWAEref] and nucleation & growth model of ZHOUref]. Main driving factors include surface condition, heat treatment, alloying composition, presence of second phase particles and irradiation. Processes to suppress nodular corrosion are presented in the present paper, for instance: increasing the Fe+Cr content, decreasing the Sn content, decreasing the annealing time and temperature, improving the surface finish. But, the most effective means of improving nodular corrosion resistance is to use a new zirconium alloy containing niobium.