This research involves a comparative study between novel dual-textured tool inserts and untextured tool inserts during CNC turning of S32750 super duplex stainless steel (SDSS), with a specific focus on nano-Minimum Quantity Lubrication (nMQL) conditions. The primary aim is to optimize the Material Removal Rate (MRR) and surface finish through a comprehensive analysis of the performance exhibited by these two categories of tool inserts. Surface texturing is an innovative green manufacturing technology that enhances the wettability of the cutting fluid at the cutting edge by modifying the surface texture of the cutting tool at the rake face. A novel dual textured tool with square and linear groove texture patterns is engraved on the tool surface using a femtosecond laser technique. The MRR and workpiece quality of a Jobber XL CNC turner used for turning operations on S32750 SDSS employing dual-textured tool inserts and untextured tool inserts were compared. In this study, each group (Control and experimental) is composed of 20 samples, yielding a cumulative sample size of 40. The calculation of the sample size is performed with a statistical power (G-power) of 80% and a significance level (alpha) set to 0.0024. The experimental results show an average surface roughness of 1.276 μm for dual-textured tools and 1.072 μm for untextured tools when turning S32750 SDSS rod. A better MRR of 13.126 cc/min is obtained when turning with dual- textured tools when compared to 10.846 cc/min with an untextured tool insert. The independent t-test results in the CNC turning process with nMQL machining conditions are statistically significant for surface roughness with a “p” value (2-tailed) of 0.001 (p < 0.05) and for MRR data, it is p = 0.0074 (p < 0.05). Based on the findings of this experimental investigation, the application of the proposed dual-textured tool insert resulted in a significant augmentation of the MRR by 17.12%, coupled with a corresponding reduction in surface roughness by 19.35%, in comparison to the utilization of the untextured carbide tool inserts.

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