Cutting fluids are utilized in machining for a selection of reasons like mitigating work-piece thermal deformation and improving the hardness of the specimen. In this work soluble oil, water and air were used as coolants in turning operations. Cemented carbide (A30 grade) and HSS (M35 grade) cutting tools were employed as cutter with cutting speed of 355rpm and Stainless Steel (SS202 grade) as the specimen. Turning was done under dry condition and also using 2 coolants. Temperature and Hardness values after each cut were recorded. The temperature readings were recorded from the tools at each case using a Digital k-type Thermocouple and the hardness of the specimens were ascertained using Rockwell Hardness test. It was revealed that variation within the Hardness value of the samples with progress in machining time is more with the use of carbide tool compared to the HSS cutter. Samples cooled with water exhibited the very best hardness value. variation within the hardness of the samples with progress in machining time is more just in case of samples machined using Carbide tool compared to HSS tool, the rationale being higher tool tip temperatures generated in carbide tool. However, in both cases, samples machined using different cutting fluids vary significantly in terms of hardness.

Keywords : Cutting Fluids, Cemented Carbide, HSS, Stainless Steel, Digital K-type Thermocouple, Rockwell Hardness Test and Soluble Oil