Co基合金涂层的制备与高温腐蚀性能研究

摘要：金属或者合金在高温条件下，可以和气氛中的氧气发生氧化反应，生成氧化层。由于氧化层特有的结构特点，可以阻断连接体基材中的铬元素向外扩散，从而防止阴极材料中毒。

合金在氧化过程中，可以生成含有多种金属的复合氧化层，例如尖晶石结构。尖晶石结构氧化层具有连续、致密、均匀等结构特点，可以阻止内部元素向外扩散和外部元素向内扩散。除此以外尖晶石结构氧化层导电性能良好，热膨胀系数与其它组件相匹配，所以能够很好附着在基材表面，对连接体形成一定的保护作用。

基于这个背景，为近一步的研究，设计了本次实验。实验研究的结果证明钴锰合金涂层在750℃的氧气环境中，预氧化20小时与100小时后形成的氧化膜的主要成分为Co3O4和MnCo2O4，以及少量Fe的氧化物。涂层与基材结合紧密，未出现明显的涂层缺陷。此外，还研究了涂层对阻止基材内部元素向外扩散的作用。实验表明，钴锰合金涂层在高温条件下能够很好地阻止Cr等元素的向外扩散，从而延长连接体的使用寿命。

关键词：燃料电池，高温腐蚀，金属连接体，钴锰涂层

Abstract：Metals or alloys at high temperatures atmosphere can be oxygen in the oxidation reaction to form the oxidation layer. Due to the structural characteristics of the oxide layer, it is possible to block the outward diffusion of the chromium element in the connector substrate, thereby preventing the cathode material from being poisoned.

Alloys In the oxidation process, a composite oxide layer containing a variety of metals, such as a spinel structure, can be formed. Spinel structure oxide layer has a continuous、dense、uniform and other structural features, can prevent the internal

elements of the external diffusion and external elements inward diffusion. In addition to the spinel structure of the oxide layer of good conductivity, thermal expansion coefficient and other components to match, it can be well attached to the surface of the substrate, the connector to form a certain protective effect.

Based on this background, in order to further study, designed this experiment. The results of the experimental study show that the main components of the oxide film of the cobalt-manganese alloy coating formed by pre-oxidation for 20 hours and 100 hours in the oxygen atmosphere at 750 ℃are the Co3O4 and MnCo2O4, and the oxides of Fe. The coating is tightly bonded to the substrate, with no significant coating defects. In addition, the effect of coating on the diffusion of elements inside the substrate was investigated. The results of experimental show that the cobalt-manganese alloy coating can prevent the outward diffusion of Ni and Cr elements under high temperature conditions, thus prolonging the service life of the linker.

Key words: SOFC; high temperature corrosion; Metal linker；Co-Mn coating;

第一章绪论 1

1.1前言 1

1.2燃料电池 1

1.3金属连接体材料 3

1.3.1Cr基合金 4

1.3.2Ni基合金 4

1.3.3铁素体不锈钢 4

1.4金属的高温腐蚀 5

1.5氧化研究 6

1.6连接体涂层材料 7

1.6.1涂层种类及制备 7

1.7高能微弧电火花沉积技术 8

1.7.1电火花沉积机理 Co基合金涂层的制备与高温腐蚀性能研究:http://www.youerw.com/cailiao/lunwen_203935.html