摘要
利用磁控反应溅射的方法在Ti_3Al基合金表面制备了两种不同铝含量的Cr_(0.82)Al_(0.18)N与Cr_(0.53)Al_(0.47)N涂层,测试了这两种涂层在800℃(Na_2SO_4+25 mass%K_2SO_4)熔融盐膜下的热腐蚀动力学,并采用X射线衍射仪和带能谱的扫描电镜分析腐蚀产物相组成以及微观结构。结果表明,两种涂层均可降低Ti_3Al基合金的热腐蚀速率;涂层热腐蚀产物主要为具有保护性的Cr_2O_3和θ-Al_2O_3混合氧化膜,θ-Al_2O_3的含量随着涂层中Al含量上升递增;和θ-Al_2O_3相比,Cr_2O_3在熔融硫酸盐中的稳定性更好,Cr_(0.82)Al_(0.18)N涂层抗热腐蚀性能优于Cr_(0.53)Al_(0.47)N涂层。
Cr0.82Al0.18N and Cr0.53Al0.47N coatings were deposited on a Ti3Al based alloy by reactive magnetron sputtering method. Hot corrosion of these two coatings in 75 mass% Na2SO4＋25 mass% K2SO4 molten salt at 800℃ was performed in a Setsys 16/18 thermoanalyzer. The phase compositions of the corrosion products were identified by X-ray diffractometer （XRD）. Both the surface and cross-sectional morphologies of the samples were observed by a scanning electron microscope （SEM）. The results showed that both Cr0.82Al0.18N and Cr0.53Al0.47N can reduce the hot corrosion rate of the Ti3Al based alloy and their hot corrosion resistance decreases with increasing aluminum content; the main corrosion products of the coatings are Cr2O3 and 9-Al2O3 and the amount of 9-Al2O3 in the corrosion products is proportional to the Al content in the coating. The better hot corrosion resistance of Cr0.82Al0.18N coating can attribute to the high stability of Cr2O3 in the molten salt.
出处
《中国腐蚀与防护学报》
CAS
CSCD
北大核心
2009年第4期306-311,共6页
Journal of Chinese Society For Corrosion and Protection
基金
国家自然科学基金资助项目(50771099)
