Study of cutting force in milling of aluminum-lithium alloy

Abstract

Abstract. Aluminum-lithium alloy has been applied to aircraft parts for reduction of the fuel consumption with its high specific strength. Cutting tests are performed to characterize the cutting force of aluminum-lithium alloy (Constellium, 2098-T8) and conventional extra-super duralumin (JIS A7075-T6) in slot milling at different spindle speeds. When the cutting speed increases, the tangential and radial components in cutting force of the aluminum-lithium alloy considerably decrease up to 300 m/min; while those of A7075 decrease monotonically. Then, the cutting process of aluminum-lithium alloy is discussed in an energy-minimum cutting force model. The shear angle and the friction angle increase with the cutting velocity, and the shear stress on the shear plane decreases with the increase of cutting velocity. According to the cutting model in milling of aluminum-lithium alloy, the cutting velocity should be taken higher than 300 m/min to not only reduce the cutting force but also control the surface finish.