| 摘要: |
| 为了研究锆合金表面 Cr 涂层的循环热冲击行为，使用自研的热冲击设备模拟循环热冲击环境，针对多弧离子镀技术制备的 Cr 涂层进行不同循环次数的热冲击试验。通过 X 射线衍射仪(XRD)和显微硬度计分别分析热冲击前后的物相变化和硬度变化，采用扫描电镜(SEM)和能谱仪(EDS)探究 Cr 涂层的表面破坏行为。循环热冲击过程中，Cr 涂层生成的氧化层有“自愈”效果，可以有效阻挡 O 进入锆合金基体，同时诱发 Cr-Zr 中间层的非均匀扩散。大量 Cr 元素的内部扩散会促使 α-Zr(O)的生成。热冲击生成的裂纹大量分布于外部氧化层、非均匀扩散的中间层以及 α-Zr(O)层。经过 N=24 次循环热冲击后，残余的 Cr 涂层仍然可以有效保护锆合金基体，避免 Zr 与大量 O 反应。通过将锆合金表面 Cr 涂层的循环热冲击行为分为三个阶段，进一步揭示了循环热冲击作用下锆合金 Cr 涂层的组织结构和抗热冲击性能的演变规律。 |
| 关键词: Cr 涂层 锆合金 热冲击 高温氧化 耐事故包壳材料 |
| DOI：10.11933/j.issn.1007-9289.20211009003 |
| 分类号:TG156;TB114 |
| 基金项目:国家自然科学基金(U1867201，U2067221)和四川省科技计划(2022JDJQ0019)资助项目 |
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| Cyclic Thermal Shock Behavior of Cr Coating on Zirconium Alloy |
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Yu Shijia1, Zhao Qingmin1, Du Peinan2, Tuo Jingyi1, Zhang Ruiqian2, Cai Zhenbing1
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1.Tribology Research Institute, Southwest Jiaotong University, Chengdu 610031 , China;2.Key Laboratory of Reactor Fuel and Materials, Nuclear Power Institute of China, Chengdu 610213 , China
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| Abstract: |
| In order to study the cyclic thermal shock behavior of the Cr coating on the surface of zirconium alloy, the self-developed thermal shock equipment is used to simulate the cyclic thermal shock environment, and the thermal shock test of the Cr coating prepared by the multi-arc ion plating technology is carried out with different cycles. The phase change and hardness change before and after thermal shock are analyzed by X-ray diffractometer (XRD) and microhardness tester, and the surface damage behavior of Cr coating is explored by scanning electron microscope (SEM) and energy spectrometer (EDS). During the cyclic thermal shock process, the oxide layer generated by the Cr coating has a “self-healing” effect, which can effectively block O from entering the zirconium alloy matrix and induce non-uniform diffusion of the Cr-Zr intermediate layer. The internal diffusion of a large amount of Cr element will promote the generation of α-Zr(O). A large number of cracks generated by thermal shock are distributed in the outer oxide layer, the non-uniformly diffused intermediate layer and the α-Zr(O) layer. After N=24 cycles of thermal shock, the residual Cr coating can still effectively protect the zirconium alloy matrix and prevent Zr from reacting with a large amount of O. By dividing the cyclic thermal shock behavior of the Cr coating on the surface of the zirconium alloy into three stages, this paper further reveals the evolution of the microstructure and thermal shock resistance of the Cr coating on the zirconium alloy under the action of the cyclic thermal shock. |
| Key words: Cr coating zirconium alloy thermal shock high temperature oxidation ATF |
