Characterization of Phases in an As-cast Copper-Manganese-Aluminum Alloy

作     者：J.Iqbal F.Hasan F.Ahmad 

作者机构：Department of Metallurgical and Materials EngineeringUniversity of Engineering and TechnologyLahorePakistan 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2006年第22卷第6期

页      面：779-784页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

主　　题：Orientation relationship DO3 structure Intermetallic phases 

摘      要：Copper-manganese-aluminum （CMA） alloys, containing small additions of Fe, Ni, and Si, exhibit good strength and remarkable corrosion resistance against sea water. The alloys are used in as-cast condition, and their microstructure can show wide variations. The morphology, crystallography and composition of the phases presented in an as-cast （CMA） alloy of nominal composition Cu-14%Mn-8%Al-3%Fe-2%Ni were investigated using optical, electron optical, and microprobe analytical techniques. The as-cast microstructure consisted of the grains of fcc α and bcc β-phases alongwith intermetallic precipitates of various morphologies. The room temperature microstructure exhibited four different types of precipitates inside the α-grains： the ＇large＇ dendritic-shaped particles and the cuboid-shaped precipitates, which were rich in Fe and Mn and had an fcc structure, while the ＇small＇ dendritic-shaped particles and the globular precipitates were based on FeaAI and had DO3 structure. These four different morphologies of intermetallic precipitates exhibited discrete orientation-relationships with the α-matrix. The β-grains only contained very small cuboid shaped precipitates, which could only be resolved through transmission electron microscopy. These precipitates were found to be based on Fe3Al and had the DO3 structure.