Effects of Atomic Oxygen on Zr-702and YZ-1Zirconium Alloy
|School||Harbin Institute of Technology|
|Keywords||atomic oxygen effect Zr-702 Zirconium alloy oxidation microstructure|
Atomic oxygen (AO) exposure test was conducted on Zr-702and YZ-1Zirconium alloy using a microwave induced atomic oxygen facility. The mass loss,surface nano-hardness, dynamic tensile property, electro-mechanical erosionresistance, residual stress and tribological property were measured for the exposedspecimens. The surface micro-morphology, chemical composition, and phaseconstitution of the exposed surface were analyzed by means of atomic forcemicroscopy (AFM), x-ray diffraction meter (XRD), scanning electron microscopy(SEM), and x-ray photoelectron spectrometer (XPS) in order to explore the erosioneffect and relevant mechanism of atomic oxygen on Zr-702and YZ-1Zirconiumalloy.The results show that, the atomic oxygen has an erosion effect on Zr-702andYZ-1Zirconium alloy resulting in mass loss and reduction of surfacemicro-roughness. Atomic oxygen exhibits little influence on tensile property andfracture behavior of Zr-702and YZ-1Zirconium alloy but increases the frictioncoefficient and wear. The electrochemical erosion resistance of Zr-702and YZ-1Zirconium alloy is improved after atomic oxygen exposure. Atomic oxygenimproves the scrath resistance of YZ-1Zirconium alloy, with increasing fluence ofatomic oxygen, the surface hardness of YZ-1Zirconium alloy firstly increases andthen decreases. Atomic oxygen decreases the surface hardness of Zr-702. Withincreasing fluence of atomic oxygen, the surface residual stress of Zr-702and/orYZ-1Zirconium alloy is firstly decreased and then increased. There are twosimultaneous and competitive processes of surface oxidation and oxide’s spallingdue to interaction of atomic oxygen, leading to nonmonotonic variation anddiscreteness of atomic oxygen effect with fluence.