An Experimental Study on Surface Roughness of Gun Material in CNC Drilling with Coated and Uncoated Carbide Tools Featuring Novel Diamond Cut Inserts

Abstract

This research investigates the surface roughness (SR) properties of gun material through CNC drilling operations utilizing both coated and uncoated carbide tools on CNC machines. The gun material, with dimensions of 10 mm thickness and 150 mm width, was prepared for machining. The experiment involved two groups with a total sample size of 20, with each group comprising 10 samples drilled with coated and uncoated carbide tools, respectively. Statistical analysis was conducted with a G-power of 80% and a significance level (P) of less than 0.05 using SPSS software. Results indicate that the minimum surface roughness was achieved with the carbide tool compared to the coated tool during CNC drilling operations. Optimal parameters for achieving this result were determined as a spindle speed of 1000 revolutions per minute, a feed rate of 0.04 millimetres per revolution, and a depth of cut of 1 millimetre. Statistical analysis demonstrated a significant distinction between the two groups, with a two-tailed significance value (p) of 0.000, below the critical threshold of 0.05, indicating a notable contrast between the effectiveness of coated and uncoated carbide tools. In conclusion, employing judicious adjustments to process variables, such as a feed rate of 0.03 mm/rev, spindle speed of 1000 rpm, and depth of cut of 2 mm, leads to superior surface roughness when utilizing coated carbide tools compared to uncoated carbide tools.