Abstract
Interfacial reactions between Mg-40Al and Mg-30Y master alloys were investigated at intervals of 25 °C in the 350–400 °C by using a diffusion couple method. Noticeable reaction layers were formed at the interfaces of the diffusion couples. The concentration profiles of the reaction layers were characterized. The diffusion path of the diffusion couple at 400 °C is constructed on the Mg-Al-Y ternary isothermal temperature phase diagram. The phases of the reaction layer were characterized by X-ray diffraction. The interfacial reaction thermodynamics of diffusion couples were studied. These results indicate that Al2Y is the only new formed intermetallic phase in the reaction layers. The growth constants of the reaction layers were calculated. In the reaction layer II, the integrated interdiffusion coefficients of Al are higher than Y, the diffusion activation energy of Y is higher than that of Al.
Highlights
Magnesium alloys are important structural materials for automotive, aircraft, and aerospace lightweighting, due to their lower densities compared with steel and aluminum [1,2]
As is seen in these micrographs, it is found that reaction layers are formed at the interfaces of diffusion couples
Most of the newly formed intermetallic phases in the reaction layer distribute along the morphology of Mg24 Y5 before diffusion
Summary
Magnesium alloys are important structural materials for automotive, aircraft, and aerospace lightweighting, due to their lower densities compared with steel and aluminum [1,2]. Adding Y to precipitate intermetallic phases in Mg-Al alloys is an efficient method to refine grain and improve the mechanical properties [3,4,5,6,7]. There have been thermodynamic and phase diagram studies on the Mg-Al-Y alloy systems. Interfacial reactions and systematic diffusion kinetics studies in Mg-Al-Y systems are not fully reported. Studies are required to evaluate the interdiffusion interactions of elements and intermetallic phases formation in the interfacial reactions between Mg-Al and Mg-Y. The interfacial reactions of (Mg-40Al)/(Mg-30Y) master alloys have been investigated at temperatures of 350–400 ◦ C by diffusion couple method. The formation of the intermetallic phases at the interface of diffusion couples has been studied. The interdiffusion coefficients of Al and Y in the diffusion reaction lays have been determined
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
