Multi-Quality Decision Using Preference Selection Index Method in Laser Trepan Cutting of Thin Electrical Steel

Laser machining has become an excellent choice for cutting thin metal substrates due to its ability to deliver high-quality cuts with minimal material waste and fast processing times. In this research, a Nd: YAG nanosecond laser was studied for cutting a hole of a thin electrical steel, with a thickness of 0.1 mm. The trepanning technique was targeted for cutting a circle with a diameter of 1 mm. The three process parameters: laser power ( P ), scanning speed ( v ), and pulse frequency ( f ) are examined to evaluate their influences on the four cutting qualities of the heat affected-zone (HAZ), height of recast layer (H R ), width of recast layer (W R ) and error of diameter (E D ). Each process parameter is elected with three levels and a total of 27 experimental datasets are achieved. Based on the experimental results, the preference selection index (PSI) method was used to determine a set of process parameters through the best cutting multi-quality. Through implementing the PSI calculation, the result shows that the best quality is found by the qualities of HAZ = 82.1 µm, H R = 17.4 µm, W R = 24.2 µm and E D = 14 µm at process parameters of P = 9 W, v = 600 mm/s, and f = 30 kHz.