CAJ | 학술논문

采用化学气相沉积（CVD）方法在单晶高温合金基体上制备了铬改性铝化物（Cr-Al）涂层，研究了1050℃下该涂层在空气中的高温氧化行为。采用X-射线衍射（XRD）、扫描电子显微镜（SEM）、能谱仪（EDS）等方法分析了Cr-Al涂层在高温氧化过程中相结构、显微组织和成分的演变规律，结果表明：经1050℃氧化300 h后，该涂层的氧化动力学曲线符合抛物线演变规律，Cr-Al涂层的涂覆提高了基体合金的抗高温氧化性能；高温氧化200 h内涂层保持良好的表面形貌，而经过300 h氧化后涂层出现了严重的氧化膜剥落现象；揭示了在高温氧化条件下 Cr-Al 涂层退化的相变过程，涂层区相结构转变过程为β-NiAl相→β-NiAl相（主）+γ′-Ni3Al相（次）；扩散区相结构转变过程为β-NiAl相+析出相→β-NiAl相（主）+γ′-Ni3Al相（次）+析出相→γ′-Ni3Al相（主）+β-NiAl相（次）+析出相→γ′-Ni3Al相+析出相。
채용화학기상침적（CVD）방법재단정고온합금기체상제비료락개성려화물（Cr-Al）도층，연구료1050℃하해도층재공기중적고온양화행위。채용X-사선연사（XRD）、소묘전자현미경（SEM）、능보의（EDS）등방법분석료Cr-Al도층재고온양화과정중상결구、현미조직화성분적연변규률，결과표명：경1050℃양화300 h후，해도층적양화동역학곡선부합포물선연변규률，Cr-Al도층적도복제고료기체합금적항고온양화성능；고온양화200 h내도층보지량호적표면형모，이경과300 h양화후도층출현료엄중적양화막박락현상；게시료재고온양화조건하 Cr-Al 도층퇴화적상변과정，도층구상결구전변과정위β-NiAl상→β-NiAl상（주）+γ′-Ni3Al상（차）；확산구상결구전변과정위β-NiAl상+석출상→β-NiAl상（주）+γ′-Ni3Al상（차）+석출상→γ′-Ni3Al상（주）+β-NiAl상（차）+석출상→γ′-Ni3Al상+석출상。
C r modified aluminide (Cr-Al) coatings were deposited by chemical vapor deposition (CVD) on the single crystal superalloy substrates and the isothermal oxidation tests were performed at 1050 ℃ to study the oxidation-resistant ability of the coatings at high temperature. The Cr-Al coatings were characterized with Scanning Electron Microscopy(SEM), X-ray Diffraction (XRD) and Energy Disperse Spectroscopy (EDS). The results show that the oxidation kinetics curve of the coating is in accord with parabolic rule after oxidation at 1050 ℃ for 300 h. The performance of oxidation resistance of the single crystal superalloy is largely improved. Cr-Al coatings′ surface still keep well after high temperature oxidation of 200 h. However, large amounts of oxide scales on the coatings′ surface have spalled along with the increase of dwelling time. The experimental results also reveal phase transition during the degradation, consisting of the coatings are β-NiAl→β-NiAl(major)+γ′-Ni3Al(minor) in outer zone and β-NiAl+precipitate→β-NiAl (major)+γ′-Ni3Al (minor)+precipitate→γ′-Ni3Al(major)+β-NiAl(minor)+precipitate→γ′-Ni3Al+precipitate in diffusion zone.