Effect of Multi-Coats of Cutting Tools on Surface Roughness in Machining AISI 1045 Steel


In this study, orthogonal machining tests in dry turning method are performed on(AISI 1045 St.), in order to examine the influences for the type and number ofcoatings on surface roughness. The cutting tools used are (TiN, TiN/TiC, andTiN/Al2O3/TiC); multiple layers coated cemented carbide inserts. The tests areperformed at five different cutting speeds (80, 112, 155, 220 and 300) m/min,while the feed rates are kept to be (0.08, 0.11, 0.14, 0.16 and 0.2) mm/revrespectively, at constant depth of cut and tool geometry. The results showed that(TiN/TiC) coated cutting tools gave best results for surface finish compared withTiN/Al2O3/TiC, TiN and uncoated tool, for all the selected machining conditions.The experimental results showed that, when the cutting speed is increased from(80-300)m/min and feed rate is reduced by (250%), the values of surface roughnessis decreased by: (20%) for uncoated tool insert ,(27%) for single coated layer insert(TiN), (55%) for double coated layer insert (TiN/TiC) and (49%) for triple coatedlayer insert (TiN/Al2O3/TiC).