Influence of Wet Micro-Shot Peening on Surface Properties and Corrosion Resistance of AISI 304 Stainless Steel

摘要

As a new developed shot peening technology, wet micro shot peening is applied to investigate theinfluence on corrosion behavior of AISI 304 stainless steel in chloride solution using potentiodynamicpolarization. Surface modifications including microstructure, residual stress, surface roughness andphase transformation are characterized. Results show that wet micro shot peening can promote theformation of deformation twins and deformation induced martensite, produce grain refinement,generate high magnitude compressive residual stress and increase surface roughness. Results ofpotentiodynamic polarization curves show that the specimen treated by lower peening pressure hasbetter corrosion resistance than those of higher peening pressure treated and as-received specimen, butthe higher peening pressure treated specimen affects inversely on the corrosion resistance with respectto as-received sample. Grain refinement and compressive residual stress induced by shot peening canenhance the corrosion resistance of AISI 304 stainless steel, but the surface roughness and deformationinduced martensite generated during shot peening decrease the corrosion resistance. Corrosionresistance of AISI 304 stainless steel in chloride solution depends on the synergy effects of thesefactors.