Effect of Molybdenum on the Microstructures of As-Cast Fe-B Alloys and Their Corrosion Resistance in Molten Zinc
Effect of Molybdenum on the Microstructures of As-Cast Fe-B Alloys and Their Corrosion Resistance in Molten Zinc
复制标题
钼对铸态Fe-B合金组织及锌液耐蚀性能的影响
DOI：
10.5006/2280
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发表时间：
2017-08-01
期刊：
影响因子：
1.6
通讯作者：
Zhao, Manxiu
中科院分区：
文献类型：
--
作者：
Ouyang, Xuemei;Chen, Guopeng;Zhao, Manxiu
研究了Mo对Fe-3.5 B合金铸态组织的影响及其在锌液中的腐蚀行为。实验结果表明，添加Mo的铸态Fe-B合金主要由α-Fe、Fe_2B、FeMo_2B_2和亚稳相Fe_3B组成。腐蚀试验表明，添加8.0wt%钼的Fe-3.5 B合金在锌液中的耐蚀性最高，这主要是因为合金仍保持硼化物的网状结构，提高了其热稳定性。当钼含量超过8.0wt%时，τ-FeMo 2B 2 + α-Fe共晶组织破坏了Fe 2B相的网状结构，导致铸态Fe-B合金的耐腐蚀性降低。在腐蚀层中发现了四种腐蚀产物（delta（p）、delta（k）、zeta和FeB）。不同Mo含量的Fe-3.5 B合金的腐蚀机理包括：α-（Fe，Mo）优先腐蚀，形成典型的Fe-Zn化合物，（Fe，Mo）（3）B和（Fe，Mo）（2）B向Fe B的转变，以及硼化物的剥落。在腐蚀过程中，钼在固体基体中不会发生扩散。腐蚀层的腐蚀深度并不严格遵循抛物线关系，可能是由于腐蚀层在锌液的侵蚀下剥落所致。腐蚀过程主要受液态锌原子的扩散控制。
The effect of Mo on the microstructure of as-cast Fe-3.5 B alloys and their corrosion behavior in molten zinc have been investigated. Experimental results show that the as-cast Fe-B alloys with molybdenum addition are mainly composed of alpha-Fe, Fe2B, FeMo2B2, and metastable Fe3B phases. Corrosion tests show that the Fe-3.5 B alloy with 8.0 wt% added molybdenum has the highest corrosion resistance in molten zinc mainly because the alloy still maintains the reticular structure of boride and improves its thermal stability. When the molybdenum content exceeds 8.0 wt%, the tau-FeMo2B2 + alpha-Fe eutectic microstructure destroys the reticular structure of the Fe2B phase, leading to reduction in the corrosion resistance of the as-cast Fe-B alloys. Four kinds of corrosion products (delta(p), delta(k), zeta, and FeB) were found in the corrosion layers. The corrosion mechanism of Fe-3.5 B alloys with various added molybdenum contents includes the following processes: the preferential corrosion of alpha-(Fe, Mo), the formation of typical Fe-Zn compounds, the transformation of (Fe, Mo)(3)B and (Fe, Mo)(2)B into FeB, and the spalling of borides. The diffusion of molybdenum in the solid matrix cannot occur in the corrosion process. The corrosion depth of the corrosion layer did not follow a parabolic relationship strictly, maybe it caused by the spalling of the corrosion layer under the attack of the liquid zinc. The corrosion process is mainly controlled by the diffusion of liquid zinc atoms.