Effect of Cutting Parameters on Surface Roughness in Dry Machining of S45C Steel Using Carbide Tools

Wet machining is still carried out in the metal cutting industry today; machining experts continue to work to reduce the use of coolant so that benefits for the environment, economy and operator safety can be obtained. The research aims to obtain cutting conditions which have a good chance of realizing the concept of dry machining on S45C steel regarding surface roughness. The research was carried out using 9 specimens by statics method with a normal distribution curve where S45C steel turning using uncoated carbide chisels was carried out on dry machining and wet machining. Machine spindle rotation of 700 rpm, 1000 rpm and 1300 rpm can be converted in the amount of cutting speed, then for infeed 0.15 mm/r, 0.2 mm/r, 0.25 mm/r and the depth of cut remains 1 mm. Machining S45C steel is selected for optimum cutting conditions on wet and dry machining. Machined surface roughness was tested using the Surface Test measuring instrument. The surface roughness obtained for dry machining was 1.602 µm, 1.667 µm and 2.041 µm for dry machining while for wet machining the results were 1.521 µm, 1.593 µm respectively and 1.915 µm. So, the most optimum cutting is obtained in cutting conditions with a cutting speed of 87.92 m/min at 700 rpm machine spindle rotation with Ra = 1.602 µm for dry machining while wet machining obtains a surface roughness value of Ra = 1.521 µm on wet machining. Comparison of the results of dry machining (Ra= 1.602 µm) and wet machining (Ra= 1.521 µm) to obtain the optimum surface roughness value Ra is not significant, so it is a good opportunity for the possibility of a dry machining technology to be applied to the metal cutting industry even though today many still use the wet machining method of turning using a cutting fluid to cut metal.

Keywords: S45C steel, cutting parameters, surface roughness, dry turning