摘要
以铜为基体,采用电镀镍和浆料包渗铝法制备出Ni2Al3渗层。研究了900℃下空气中不同氧化时间,Ni2Al3渗层的高温抗氧化性能与组织转变行为。结果表明:经电镀Ni及随后800℃×12h浆料包渗铝,可在铜表面获得厚度为250μm、物相单一的致密Ni2Al3渗层。900℃氧化实验过程中,氧化时间在100h内,渗层表面X射线衍射分析中,没有Al2O3相衍射峰产生,Ni/Ni2Al3界面的Ni2Al3相首先转变为NiAl相,并且NiAl相随时间延长而增厚;超过150h后,在渗层中Al2O3相出现衍射峰,同时Ni2Al3相全部转变成NiAl相。在高温氧化过程中渗层无明显剥落现象,到250h时渗层仍具有良好的抗高温氧化性能,渗层表面由NiAl相和Al2O3相组成。
Ni2Al3 coating was fabricated on copper by electro-depositing nickel and then aluminizing by a slurry pack cementation process.High temperature oxidation behavior and microstructure evolution of Ni2Al3 coating at 900℃ in air for different time were investigated.The results show that the single phase Ni2Al3 coating with thickness of 250μm is obtained on copper.After oxidizing at 900℃ for less than 100 h,there are no any diffraction peaks of oxide observed on the surface of Ni2Al3 coating based on XRD analysis.However,the Ni2Al3 phase at the interface between Ni plating and Ni2Al3 coating is changed into NiAl phase.The thickness of NiAl coating increases with increasing oxidizing time.θ-Al2O3 phase is found on the coating surface and all Ni2Al3 is changed into NiAl phase after oxidation at 900℃ for 150 h.No spallation of the coating occurs during the oxidation process.The coating is mainly composed of NiAl and θ-Al2O3 and shows an excellent high temperature oxidation resistance after oxidation at 900℃ for 250 h.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2008年第2期166-170,共5页
Transactions of Materials and Heat Treatment
基金
东南大学自然科学基金项目(9212002232)
