The Effect of Cutting Fluid Condition on Surface Roughness in Turning of Alloy Steel

During machining processes heat is generated. The use of a cutting fluid provides lubrication and cooling effects which improve the final quality of the workpiece. Nevertheless, cutting fluid application provides some problems involving costs, environmental and health issues. In this paper, the relationship between the cutting lubricant and the surface roughness of 4340 alloy steel using three different lubricant conditions; i.e. dry machining, minimum quantity lubrication (MQL) and wet machining, is investigated. The turning parameters include the cutting speed, feed rate, cutting depth and time were considered using a carbide insert (CNMG 12 04 08-QM) H13A for light and medium turning. Then, the effects of these parameters on the surface roughness were studied. The results shows that the surface roughness is the best when using MQL on the light turning followed by wet and dry machining. Meanwhile for medium turning, the preferred condition is wet machining compared to MQL and dry machining.