Investigation and Modeling of Ball-Burnishing Factors Affecting Residual Stress of AISI 8620 Steel

Abstract

Ball-burnishing is a super finishing, chipless operation employs plastic deformation to improve surface and subsurface integrity. This work created a model to confirm that ballburnishing of AISI 8620 steel affected its microstructures, roughness, and residual stress which can directly enhance the performance and the quality of the steel. Burnishing of hard metallic surfaces opens an alternative to grinding, the main advantage being the low cost, claimed to be 8-15 times less expensive than grinding. Birdstrike, bird ingestion (for an engine) is a collision between birds and aircraft are a significant threat to flight safety and have caused a number of accidents with human casualties. Using the AISI 8620 steel with its high mechanical properties after the burnishing operation in the aeroengine can reduce such as threat; nevertheless, the effects of the ball burnishing of the AISI 8620 steel has not been well studied. This research, the influence of different parameters on the residual stress surface in the axial direction was investigated. Samples were prepared by heat treatment and turning. The iv ball burnishing prosses was performed, and the improvements on the surface and subsurface integrity were significant. Residual stress after ball-burnishing was found to be affected by pressure and feed rate to a statistically significant extent. Stress is found to be in the form of compression. Steel displayed roughly a 60% improvement in surface roughness following burnishing. The linear empirical regression model derived from the data for the relationship between burnishing factors and residual stress offer R2 values of 80.88%. With this result, the AISI 8620 steel has enhanced its properties after the ball burnishing process.