A force model of turning stainless steel with worn tools having nose radius

To study cutting forces, tip’s surface temperature, the mechanism of secondary chip and main chip formation when turning stainless steel with a chamfered main cutting nose radius tool are considered to have pre-wear. A holder with special tools and geometry are designed first. Secondly, the tool holders made of medium carbon steel bars are milled and ground to make them fit to various specifications. Finally, the tip’s mounting in the tool holder are ground to wearing depth measured with a toolmaker’s microscope and a new force model incorporating a tool pre-wear factor using the variations of shear plane areas cooperating with tool pre-wear situations is made. After the cutting processes have occurred, more wear factors of tool are considered in the force model. For successfully predicting cutting forces, however, shear plane areas vary due to the wearing effects of the tool edge in cutting stainless steel.