The effect of cutting tool surface coating and lubricant on the machining process

Machining is the process of cutting tools to give the final dimensions and tolerances to the workpiece. Machining is used many areas from the automotive industry to the mold industry. The basic principle of machining is the action of the cutting tool to remove chips from the workpiece surface acquired force and feed. Machine tools vary acoording to the condition of the workpiece, cutting tools and final dimensions. Chips formed after machining, cutting tool cutting edges, workpiece surface roughness and workpiece dimensions are among the improvement issues of machining. In this thesis study, first of all, dry machining conditions without cooling, emulsion cooling with %3 boron oil and emulsion cooling conditions %5 boron oil were compared. Machining was carried out on two different workpieces, as a face milling operation of CuZn39PbAl-C (CC757S) brass alloy and AISI 1040 steel. The face milling operation was performed on a vertical machining centre using AlCrN coated end mills under the same conditions as uncoated tungsten carbide end mills with diameter 8 mm, 4 cutting edges. The workpieces were evaulated separately in terms of both cooling condition and AlCrN coated and uncoated end mills. Evaulations are based on machine tool energy consumption, workpiece hardness, surface roughness and cutting tool and chip results. As a result of the study, it was seen that dry cutting conditions gave negative results in the machining of each workpiece, while %3 boron oil cooling conditions gave close and more positive results than %5 boron oil cooling conditions. In addition the data obtained from AlCrN coated cutting tools gave better results in terms of energy consumption, surface roughness, surface hardness and tool life. At the end, the best machining conditions were observed for brass alloy with AlCrN coated end mills in %3 boron oil cooling conditions, and for AISI 1040 steel with AlCrN coated end mills in %3 boron oil cooling conditions.