The Influence of Ion Beam Surface Microalloying on the Cyclic Deformation of Nickel-Aluminum Alloys

本研究的目的是研究离子束改性对Ni-Al合金循环变形行为和导致疲劳裂纹萌生的近表面损伤积累过程的影响。从纯镍单晶到Ni3Al镍铝金属间化合物的材料都被离子注入（用于合金化或离子束混合），并使用卢瑟福后向散射、离子通道和透射电子显微镜对材料进行表征。机械性能研究将包括分析表面残余应力和硬度，表面损伤累积作为塑性应变的函数，以及疲劳裂纹的起始。

The objective of this research program is to investigate the influence of ion beam modification on the cyclic deformation behavior and resulting near-surface damage accumulation processes which lead to fatigue crack initiation in Ni-Al alloys. Materials ranging from pure nickel single crystals to the Ni3Al nickel-aluminum intermetallic compound are being ion implanted (for alloying or ion beam mixing) and the materials are being characterized using Rutherford backscattering, ion channeling, and transmission electron microscopy. Mechanical property studies will include analyses of surface residual stresses and hardness, surface damage accumulation as a function of plastic strain, and fatigue crack initiation.