Superficial Residual Stresses in Face-Milling the 17-4PH Stainless Steel at Various Feed Rates

17-4PH stainless steel is a widely used martensitic precipitation hardening stainless steel, and it is a typical difficult-to-cut material. Residual stress is an important part of the surface integrity. In this paper, superficial residual stress tests of face-milling the 17-4PH stainless steel were carried out at 0.1~0.3 mm/tooth with TiAlN coated carbide inserts. The effects of feed rate on the superficial residual stresses at various cutting speeds were studied. It was found that the residual stresses on the machined surface were very sensitive to the feed rate. The superficial residual stresses at the directions of parallel to and normal to the feed direction both remained compressive and changed obviously in higher compressive direction along with the feed rate. The burnishing effect determined by the cutting force was found to be the primary reason of the residual compressive stresses on the machined surface. The suitable cutting parameters were recommended according to the superficial residual stresses.