CORROSION/DEFORMATION INTERACTIONS IN URANIUM/WATER SYSTEMS
Arie BUSSIBA, Henry ALUSH and Yosef KATZ
Abstract:Aqueous corrosion/Deformation Interactions (ACDI) in uranium and uranium alloys actually exhibit complicated mechanical damage processes. In this context, the exploration of the dominant micromechanical mechanisms vis-a vis experimental confirmations remain an unsettled issue. Various mechanisms might be involved in such environmental effects, starting from stress corrosion cracking (SCC) hydrogen embrittlement, up to brittle film fracture or film-induced cleavage, enhanced or inhibited by diffusion barriers. These on top or hybrid formation which potentially affects the local mechanical/chemical driving field. Thus, beside the driving force modifications, the reduction of the fracture resistance requires appropriate evaluations. The main objective in the current phenomenological investigation was, to provide additional findings as related to damage evolution in specific ACDI systems. In fact, the present selected systems allowed further insights into a low symmetry, orthorhombic crystal structure case. Experimentally, sustained load, slow strain rate (SSR), monotonic and fatigue tests in fracture mechanics framework were performed, supplemented by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) observations. In addition, X-ray, Fourier Transform Infrared spectroscopy (FTIR) techniques and acoustic emission (AE) tracking were utilized. Experimental findings are analyzed and discussed with emphasis to fractographic observations and kinetics associated with the crack propagation stage. These beside development in modeling aspects founded on a stepwise decohesion processes. Key Words:Corrosion-deformation interaction, Uranium-water, Slow strain rate test, Stress corrosion cracking, Fatigue crack propagation, Hydrogen embrittlement, Decohesion