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Sheet metals such as titanium alloys, steel alloys, and aluminum alloys are significant materials due to their importance among everyday life products as well as high-strength applications in aircraft, ships, automobiles, construction, military, and marine purposes. Recently, laser cutting is one of the best and fastest non-conventional methods to cut sheet metals, so it is necessary to understand how laser cutting parameters affect cutting quality. A comprehensive review was presented to investigate how laser cutting parameters affect the cut surface and kerf quality and which parameters affect cutting quality the most. An overview of the advantages of laser cutting when compared to other methods of machining was presented. In addition, a description of the laser cutting method and the different sources of laser were presented with clearing the range of thicknesses of the cut material for each source and their advantages. Also, a description of the properties and the applications of the studied materials were discussed. The performance parameters ofcutting were illustrated in detail by graphs and equations. The research analysis and discussion were discussed in such organized details by tables and graphs which show the full classification of the studied papers. It was found that the best conditions to obtain low surface roughness, small HAZ width, small kerf width, and small kerf angle are using low laser power, high cutting speed, medium gas pressure, high standoff distance, medium pulse frequency, medium pulse width, small nozzle diameter, small thickness, and nitrogen as an assist gas. [ABSTRACT FROM AUTHOR]

In this paper, an enhanced random vector functional link network (RVFL) algorithm was employed to predict kerf quality indices during CO2 laser cutting of polymethylmethacrylate (PMMA) sheets. In the proposed model, the equilibrium optimizer (EO) is used to augment the prediction capability of RVFL via selecting the optimal values of RVFL parameters. The predicting model includes four input variables: gas pressure, sheet thickness, laser power, and cutting speed, and five kerf quality indices: rough zone ratio, widths of up and down heat affected zones, maximum surface roughness, and kerf taper angle. The experiments were designed using Taguchi L18 orthogonal array. The kerf surface contains three main zones: rough, transient, and smooth zones. The results of conventional RVFL as well as modified RVFL-EO algorithms were compared with experimental ones. Seven statistical criteria were used to assess the performance of the proposed algorithms. The results indicate that the RVFL-EO model has the predicting ability to estimate the laser-cutting characteristics of PMMA sheet. [ABSTRACT FROM AUTHOR]

Titanium alloys, especially Ti–6Al–4 V alloy, are significant materials because of their superior mechanical and chemical properties. They are used in most high-strength and elevated temperature applications, such as aircraft, ships, biomedicine, and marine applications. Recently, laser machines were used to cut a variety of sheet metals. It is critical to comprehend how laser cutting parameters influence surface and kerf quality. In this work, a 4 mm-thick Ti–6Al–4 V sheet was cut. Laser beam power, cutting velocity, and assist gas pressure were used as cutting parameters, while surface roughness, kerf width, taper angle, and dross height were measured to determine which parameter has the greatest influence on the cutting quality. It was found that laser power of 3 kW, cutting velocity of 2000 mm/min, and assist gas pressure of 8 bar were the optimized parameters to achieve the minimum surface roughness value of 2.34 ± 0.12 µm and the minimum dross value of 0.270 mm due to the high velocity. The minimum value of kerf width was found to be 0.774 ± 0.016 mm at upper surface and 0.408 ± 0.039 mm at lower surface of cut at cutting conditions of Pu = 2.5 kW, V = 1500 mm/min, and assist gas pressure of 10 bar. The minimum value of kerf taper was found to be 1.89 ± 0.61° at cutting conditions of Pu = 2 kW, V = 1500 mm/min, and assist gas pressure of 8 bar. [ABSTRACT FROM AUTHOR]