Effect of cryogenic treatment on coated and uncoated carbide inserts during turning and facing of alloy steel using Taguchi method

The manufacturing sector is under intense pressure to improve product quality and productivity while reducing production costs due to the rising cost of complex products. The performance of the cutting tool was much improved after the carbide inserts were coated with CVD. As it is customary in the industry, ISO P-20 coated insert grades were utilized for the studies. Cryogenic treatment was applied to the carbide inserts by bringing the temperature down to -186 °C. Frozen tungsten carbide inserts have a longer lifespan, according to the research. In order to determine the impact of cryogenic treatment on the toughness and tool life of coated and uncoated carbide inserts used to turn alloy steel, we utilised the Taguchi technique to consider both technical and economic aspects. The efficiency was tested using Taguchi orthogonal array L16, taking into account feed rate, cutting speed, insert coating, and tool type. While turning continuously, the effect of cutting speed was 18.01% and when facing intermittently, it was 9.45%. This was achieved using inserts coated with a sandwich layer of Al₂O₃ and TiC, with a thickness of 18.3 microns, on EN24 grade alloy steel with BHN values ranging from 234 to 236. While the feed rate contributed to 16.47% during intermittent facing operation, it was 21.66% in the continuous turning operation. When compared to untreated inserts, those that have been cryogenically treated had a 66.79% longer life during intermittent facing. At A₂B₂C₁ parameters the inserts wear study shown that, the tool life of cryogenic treated coated carbide inserts found 42.81% higher than untreated coated carbide inserts for the same tool wear. Tempering of cryogenic-treated inserts at 200 °C for 150 min, resulted to 46.53% higher when compared to untreated coated carbide inserts in the continuous turning test and 71.44% higher in the intermittent facing trial compared to untreated coated carbide inserts.