An experimental investigation of the effect of lubrication method on surface roughness and cutting fluid consumption in machining of superalloys

Super alloys due to special features such as high resistance to corrosion and heat, have the ability to maintain mechanical and chemical properties at extremely high temperatures which used in various industries, especially in the aerospace industry. On the other hand, very low heat transfer coefficient, high toughness with work hardening in these alloys caused the machining of them is seriously challenged. In the present study, the effect of cutting parameters on surface roughness of A286 superalloy has been studied in different lubrication conditions. Response surface method experimental design was used to plan experiments. In order to investigate the effects of machining parameters and conditions of lubrication on the surface roughness, Two factors - cutting speed and feed rate- on three levels and minimum quantity lubrication conditions and wet method are considered as the main parameters too. In order to investigate the Tool wear and workpiece surface quality, the images of Scanning Electron Microscope and optical microscope are used. The results show that using of the minimum quantity method of lubricant is caused to increase cooling-lubrication fluid particles penetrating power to the cutting zone and improves the process by reducing the surface roughness. It was observed that with increasing feed rate in fixed cutting speed, numerical values of surface roughness in Ra criterion are taken apart for different lubrication circumstances and its value for the minimum quantity method of lubricant is less, which shows the superiority of this method over the wet method.