NiCrAlYSi涂层/DD6单晶高温合金界面再结晶和互扩散行为研究

changjunjie1985

【作者】 姚锐； 郭洪波； 彭徽； 宫声凯；

【Author】 Yao Rui, Guo Hongbo, Peng Hui, Gong Shengkai (School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191,China)

【通讯作者】 郭洪波
【机构】 北京航空航天大学材料科学与工程学院；
【摘要】 采用电子束物理气相沉积(EB-PVD)在单晶高温合金DD6基体上沉积NiCrAlYSi涂层。利用X射线衍射(XRD)、扫描电镜(SEM)、能谱仪(EDS)以及透射电镜(TEM)等研究了高温扩散过程中NiCrAlYSi/DD6的界面再结晶和互扩散行为。研究结果表明合金表面喷砂处理后的涂层试样经1323K真空热处理4小时后,在涂层/合金基体界面出现了厚度约为7μm的胞状再结晶区;表面未喷砂处理的涂层试样经过50h后没有出现再结晶,经过75h后形成了厚度约为15μm的再结晶区。在大气中静态氧化500h后,表面未喷砂处理试样在涂层/合金界面形成了厚度约为28μm的再结晶区,同时在合金基体中形成了厚度约60μm、以针状TCP相为主的二次反应区(SRZ),TCP相富含W、Re、Ta。 [url=]更多[/url][url=]还原[/url]

【Abstract】 In this paper, the NiCrAlYSi coatings were deposited by electron beam physical vapor deposition (EBPVD) on nickel-based single crystal superalloy DD6. Inter-diffusion and re-crystallization behaviors at the coating/superalloy interface of the coated superalloy substrates were investigated at 1323 K by X-ray diffraction (XRD),scanning electron microscopy (SEM) equipped with energy dispersive spectrometry (EDS) and transmission electronmicroscopy (TEM). The results indicate that a re-crystallization zone of ~7μm thickness was formed at the coating/substrate interface of the blasted sample after 4 h vacuum heat-treatment at 1323 K. Such re-crystallization zone was not observed in the unblasted sample even after 50 h heat-treatment. However, a re-crystallization zone of ~15 μm thickness was formed in the sample after 75 h. After 500 h isothermal oxidation in air at 1323 K, a recrystallization zone of ~28μm thickness was formed in the unblasted sample. Besides, a so-called secondary reaction zone of ~60μm ,basically consisting of topologically close-packed phase (TCP) needles, was formed in the superalloy. The precipitate of TCP was enriched in W, Re and Ta