(中国航发沈阳发动机研究所，沈阳 110015)
摘 要: 镍基高温合金DD5、DD10和DSM11在涂覆10%NaCl+90%Na2SO4(质量分数)混合盐膜后进行(850 ℃，200 h)热腐蚀实验，并利用扫描电子显微镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)等分析手段，对腐蚀200 h后的合金进行热腐蚀行为对比分析。结果表明：DD10和DSM11合金成分中含有较高含量的Cr和Ti，在表面易生成保护性Cr2O3和TiO2氧化膜，氧化膜遇到熔盐中的O2-会优先在表面发生溶解，保证内部Al2O3氧化膜的稳定生长，进一步抑制热腐蚀反应的进行，提高合金的抗热腐蚀性能。DD5合金中Cr和Al含量较少且相差不大，在合金表面形成Cr2O3和Al2O3混合型氧化物，导致内部元素的贫化，不易形成连续致密性氧化膜，基体会进一步遭受到腐蚀。
关键字: 镍基高温合金；DD5；DD10；DSM11；热腐蚀；氧化膜
（Shenyang Aeroengine Research Institute, Aero Engine Corporation of China, Shenyang 110015, China）
Abstract:The hot corrosion behaviors of Ni-base superalloy DD5, DD10 and DSM11 in the presence of 10%NaCl+90%Na2SO4 (mass fraction) salt film after corrosion at 850 ℃ for 200 h were tested by scanning electron microscopy(SEM), energy disperse spectroscopy(EDS) and X-ray diffraction(XRD). The results show that O2- in molten salt preferentially reacts with the outside Cr2O3 and TiO2 layer at surface of the alloys DD10 and DSM11 owing to the high Cr and Ti contents. DD10 and DSM11 have excellent thermal corrosion resistance, the further corrosion of alloy enable to be inhibited because of stable growth of Al2O3. The outside Cr2O3 and Al2O3 layer at surface of the alloy DD5 owing to the fewer and similar Cr and Al contents can cause the dilution of internal alloy elements. The alloy DD5 cannot form a continuous oxidation film, the base metal will suffer further corrosion.
Key words: Ni-base superalloy; DD5; DD10; DSM11; hot corrosion; oxidation film
