Experimental investigation of the effect of tool geometry on residual stresses in high speed milling 7050-T7451 aluminium alloy

The effects of tool geometry on residual stress distribution in the machined surface and subsurface of Al 7050-T751 were experimentally investigated. In the experiments, the residual stresses were measured by using X-ray diffraction technique in combination with electro-polishing technique. The results showed that the subsurface residual stresses generated in the end-milling cutting processes were compressive; and the nose radius, rake/relief angle and diameter of the solid end mill had a significant effect on residual stresses profiles. The dynamometer Kistler 9257A was used to measure the milling force, which was helpful to explain the phenomenon of machining induced residual stress.