| 引用本文: | 王盼航,余竹焕,张洋,刘蓓蕾.预氧化对一种镍基单晶高温合金的热腐蚀影响[J].材料科学与工艺,2018,26(6):36-42.DOI:10.11951/j.issn.1005-0299.20170428. |
| WANG Panhang,YU Zhuhuan,ZHANG Yang,LIU Beilei.Effect of pre-oxidation on hot corrosion of a nickel-base superalloy[J].Materials Science and Technology,2018,26(6):36-42.DOI:10.11951/j.issn.1005-0299.20170428. |
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| 摘要: |
| 为了解预氧化对镍基单晶高温合金的短时热腐蚀影响，采用涂盐法研究了一种高温合金经预氧化后在Na2SO4-NaCl盐膜条件下的热腐蚀行为，测量了不同预氧化处理时间合金的腐蚀动力学曲线，借助扫描电子显微镜(SEM)观察了合金腐蚀层截面的微观组织，并利用X-射线衍射仪(XRD)确定相结构.结果表明：未经过预氧化处理的合金表面腐蚀严重，热腐蚀增重质量最多达到0.033 mg/cm2，其腐蚀动力学曲线遵循抛物线规律，而经过预氧化处理后合金表面腐蚀明显改善；合金在900 ℃下的热腐蚀符合硫化氧化模型，腐蚀产物出现了分层结构；合金的主要腐蚀产物是NiO、Al2O3以及少量NiCr2O4、TiO2、NiS2等, 其中Al2O3、TiO2等氧化物位于氧化层最外层；预氧化生成的Al2O3层对高温合金在Na2SO4-NaCl盐膜下的短时热腐蚀有明显的保护作用，腐蚀层厚度从170 μm降低至80 μm.致密的氧化物保护层能够显著阻止硫元素的扩散，提高合金的耐热腐蚀性能.
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| 关键词: 镍基高温合金 预氧化 热腐蚀:Na2SO4-NaCl 硫化氧化模型 |
| DOI：10.11951/j.issn.1005-0299.20170428 |
| 分类号:TG174.45 |
| 文献标识码:A |
| 基金项目:国家自然科学基金项目(51201130)；陕西省教育厅专项科研计划项目(15JK1487). |
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| Effect of pre-oxidation on hot corrosion of a nickel-base superalloy |
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WANG Panhang,YU Zhuhuan,ZHANG Yang,LIU Beilei
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(College of Material Science and Engineering,Xi′an University of Science and Technology,Xi′an 710054, China)
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| Abstract: |
| To understand the effect of pre-oxidation on short-term hot corrosion of nickel-based single crystal superalloys, salt corrosion method was used to study the hot corrosion behavior of a superalloy after pre-oxidation under Na2SO4-NaCl salt solution. The corrosion kinetics curves of different pre-oxidation treatment time of the alloy were measured, the microstructure of the cross-section of the alloy corrosion layer was observed with a scanning electron microscope (SEM), and the phase structure was confirmed by X-ray diffraction (XRD). The result showed that the alloy surface without pre-oxidation was severely corroded, hot corrosion weight gain reached the maximum mass 0.033 mg/cm2, and the corrosion kinetic curve followed the parabolic law. After pre-oxidation treatment, the corrosion of the alloy surface was obviously improved, the hot corrosion of the alloy at 900 ℃ accorded with the model of sulfurization oxidation, and corrosion products appeared layered structure. The main corrosion products of the alloy were NiO, Al2O3, a small amount of NiCr2O4, TiO2, NiS2, and so on, among which oxides such as Al2O3, TiO2 located on the outermost layer of the oxide layer. The pre-oxidized Al2O3 layer had a significant protective effect on short-term hot corrosion of superalloy under Na2SO4-NaCl salt film.The thickness of the etching layer was reduced from 170 μm to 80 μm. A dense oxide layer could significantly prevent the diffusion of sulfur and improve the hot corrosion resistance of the tested alloy.
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| Key words: nickel-base superalloy pre-oxidation hot corrosion Na2SO4-NaCl model of sulfurization oxidation |
