Fretting wear behavior of nitrogen implanted Zircaloy-4alloy①
(1. Department of Materials Science and Engineering, Tsinghua University, Beijing100084, P.R.China;
2. Department of Metallurgical Engineering, Sung Kyun Kwan University, South Korea;
3. Korea Atomic Energy Research Institute, South Korea)
2. Department of Metallurgical Engineering, Sung Kyun Kwan University, South Korea;
3. Korea Atomic Energy Research Institute, South Korea)
Abstract: Zircaloy-4 was implanted with nitrogen at 120keV with various ion doses between 1×1013and 1×1014ions/m2. Fretting wear tests were performed at various cycles and loads under water immersion condition by the fretting simulator, The implanted surfaces were analyzed by Auger electron spectroscopy (AES) and transmission electron microscope (TEM). Micro-hardness tester measured surface hardness. It is shown that nitrogen implantation produced Zirconium nitride oxide and high density dislocations in implanted layer, surface hardness was enhanced from HK280 for unimplanted specimen to HK1800 for a total ion dose of 1×1014ions/m2. The nitrogen ion implantation treatment provided significant improvements in the resistance of fretting damage.
Key words: Zircaloy-4; fretting wear; surface hardness; nitrogen implantation