Papers by Keyword: High-Energy Shot-Peening

Abstract: High-energy shot-peening on H13 steel after quenched. The samples with or without high-energy shot-peening were ion-nitrided at 520°C for 3h．The Microstructure，nitriding depth, hardness gradient, surface phase and Corrosion resistance of the nitride layers were compared between the high-energy shot-peening samples and the original samples using optical microscope, micro-hardness tester, X-ray diffraction and CH1660A electrochemical test. Results show that the high-energy shot-peening greatly speeds up the nitriding on the H13 steel at 520°C for 3h.. The depth of ion-nitriding layer after shot peening is from 0.11mm to 0.16mm, micro-hardness of the surface layer is from 998HV0.5 to 1105HV0.5, The hardness gradient is slightly flat . Phase structure and content of the surface is different by Powerful shot-peening and not. Corrosion resistance of the samples by high-energy shot-peening is significantly improved because it is easier to form a stable passive film.

Abstract: The paper investigated nano-crystallization on surface layer of commercial pure titanium by using high-energy shot peening. The grain size and the microstructure in deformed surface layer by high-energy shot peening are analyzed with X-ray diffraction and TEM etc. In addition, the variations of surface microhardness are examined after high-energy shot peening. The results described that the nano-crystalline surface layer have been formed in commercial pure titanium with a structure of hexagonal closet packet, by high-energy shot peening. The surface microhardness increases and the grain size in nano-crystalline surface layer diminishes, with increasing the time in high-energy shot peening. The minimum nano-crystalline grain size is approximately 40 nm.