laser parameter study on cutting metal using CO2 laser

This experimental study investigated for the effect of laser parameters on machining of the SS41 and SUS304. 8 These materials play an importance role in engineering aspect. They are widely used in high-tech industries such as 9 aerospace, automotive, and semiconductor. Due to the development of technology and high-tech industrialization, the 10 various processing technologies requiring high precision are being developed. However, the conventional cutting process 11 is difficult to meet high precision processing. Therefore, to achieve high precision processing of the SS41 and SUS304, 12 laser manufacturing has been applied. The experiment investigates the process quality of laser cutting for SS41 and SUS304, 13 with the usage of a continuous wave CO 2 laser cutting system. The experimental variables are set to the laser cutting speed, 14 laser power, and different used materials. The results are significantly affected by the laser parameters. As the results, the 15 process quality of the laser cutting has been observed by measuring the top and bottom kerf widths, as well as the size of 16 the melting zone and HAZ according to E line . In addition, the evaluation of the laser processing parameters is significantly 17 important to achieve optimal cutting quality. Therefore, we observed the correlation between the laser parameters and 18 cutting quality. These were evaluated by analysis of variance (ANOVA) and multiple regression analysis.


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SS41 is a structural steel containing Si and Mn. It is widely used in various fields such as 28 aerospace, automobiles, ships, and construction due to its low cost. SUS304 has high corrosion 29 resistance due to containing Cr component. These metallic materials characterize with low thermal 30 deformation therefore, it is generally used for various applications without surface treatment. 31 However, it is challenging issue to machine SS41 and SUS304 with high precision processing using 32 conventional technique. Thus, the manufacturer prefers to use high-power laser processing rather than 33 mechanical processing. Besides, it is supported to conventional machining in order to improve 34 machinability. The laser processing has more advantages than mechanical processing. Laser 35 machining can be performed on various materials, without tool wear and additional cost. The method 36 is non-contact processing, which provides flexibility in processing. [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The manufacturers using 37 high-power laser processing are concerned for the optimize the quality and productivity of the 38 products. However, to improve product quality and productivity, the effects of laser parameters on the 39 material should be considered as major issue. In addition, in order to control the influence of the laser 40 beam, the laser parameters must be selected appropriately. Indeed, adjustable laser parameters include 41 laser power, cutting speed, assist gas pressure and stand-off distance. 42 To maintain high precision and good quality process, the laser parameters applied to the 43 process should be properly selected, but the effect of the parameters is difficult to predict. Besides, 44 many manufacturers spend a lot of time and effort to determine the laser parameter which is suitable 45 to apply for the process. In the previous studies, experiments were carried out according to specific 46 laser parameters, and there was a comparative analysis of the effect of each parameter on the 47 processing quality. Lamikiz  demonstrates the experiment of laser cutting on 304 stainless steel miniature gear. In the experiment, 60 The CO2 laser system was employed to cut the miniature. The effects of laser parameters on average 61 surface roughness (Ra) has been investigated the surface of craters and cracks.

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In the previous studies have done significant investigation on the influence of laser 63 parameters in laser cutting process to the materials. However, it is determined that not only the 64 influence of each parameter but also the interaction between the parameters can affect the high -65 power laser processing for the different metallic materials. Therefore, this study predicted and 66 analyzed the effect of high-power laser parameters on the different metallic materials. Multiple 67 regression and analysis of variance (ANOVA) are used to predict the kerf width, melting width, and 68 heat affected zones generated after laser cutting. In addition, these are used to investigate the effects 69 of parameter and interaction between parameters. In the present study, a continuous wavelength CO 2 laser was used for the cutting process.

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During the experiment, the stand-off distance of the laser is constant, and the nozzle size is fixed at 74 0.2 mm. In addition, assistance gas is used by the constant pressure of N 2 and O 2 to maintain high 75 processing quality. Table 1 shows the laser parameters applied to SS41 and SUS304. Different laser 76 powers and cutting speeds were conducted to cut the materials in the experiment. In the parameters 77 applied to the experiments, if they are outside the set range, each material was not cut. Therefore, the 78 parameters shown in Table 1 are applied for laser cutting process. Table 2     where, P laser is the laser power, V s is the cutting speed, A is the spot size of the laser beam.

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Experimental results are analyzed through E line to identify the effect on the laser powers and cutting 94 speed that changed during the experiment.
Where, β is the regression coefficient and can be calculated using least-squares method, X i and X j are  The regression model for kerf widths and melting width on SS41 is shown in Figure 6.    variable has a statistically significant effect on the experimental data. Table 5 and Table 6 for

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The ANOVA results for SS41 are shown in Table 5. In each ANOVA The influences of the laser parameter such as laser power and cutting speed on the SS41 and