Abstract
With the full use of combustion heat from Fe-O reaction, laser-assisted oxygen cutting (LASOX) is able to cut thick mild steel plates by a defocused laser of medium power (approximately 1 kW). The dynamic behavior of oxygen gas flow, determined by nozzle structure and cutting parameters, is the key factor affecting cut ability and quality. It is significant to understand the method to design a suitable supersonic nozzle and to evaluate its performance. A supersonic minimum length nozzle (MLN) was designed and made specially for LASOX. The configuration (D exit/D critical) of the designed nozzle was chosen based on two-dimensional isentropic calculation of dynamic gas pressure. The divergent section of the MLN was designed in accordance with the method of characteristics (MOC). Numerical simulation and Schlieren visualization were used to observe and compare the flow behavior of the free jet from the designed MLN nozzle and a commercial supersonic nozzle. The MLN nozzle generates a highly uniform and stable supersonic jet extending a longer distance along the axis of nozzle, which is around 1.4 times longer than that from the commercial supersonic nozzle. Mild steel plates in 20 mm thickness were cut to investigate the effect of cutting parameters on LASOX cut quality of two nozzles. The MLN significantly improved cutting quality due to the better performance of gas flow. The optimal cut quality is related to both oxygen pressure and cutting speed. The oxygen content was measured along the cut surface to explain the difference in cut quality.
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References
Malikov AGE, Orishich AM, Shulyat'ev VB (2009) Experimental optimization of the gas-assisted laser cutting of thick steel sheets. Quantum Electron 39(6):547
Schulz W, Hertzler C (2004) Cutting: modeling and data in laser applications. Springer, Berlin Heidelberg, pp 187–218
Kovalev OB, Yudin PV, Zaitsev AV (2009) Modeling of flow separation of assist gas as applied to laser cutting of thick sheet metal. Appl Math Model 33(9):3730–3745
Schulz W, Nießen M, Eppelt U, Kowalick K (2009) Simulation of laser cutting. In The theory of laser materials processing. Springer Netherlands: 21-69
Ivarson A, Powell J, Magnusson C (1996) The role of oxygen pressure in laser cutting mild steels. J Laser Appl 8(4):191–196
Yao YL, Chen H, Zhang W (2005) Time scale effects in laser material removal: a review. Int J Adv Manuf Technol 26(5-6):598–608
Chen K, Yao YL, Modi V (1999) Numerical simulation of oxidation effects in the laser cutting process. Int J Adv Manuf Technol 15(11):835–842
O’Neill W, Gabzdyl JT (2000) New developments in laser-assisted oxygen cutting. Opt Lasers Eng 34(4):355–367
Sundar M, Nath AK, Bandyopadhyay DK, Chaudhuri SP, Dey PK, Misra D (2009) Effect of process parameters on the cutting quality in lasox cutting of mild steel. Int J Adv Manuf Technol 40(9-10):865–874
Chaki S, Ghosal S (2011) Application of an optimized SA-ANN hybrid model for parametric modeling and optimization of LASOX cutting of mild steel. Prod Eng 5(3):251–262
Man HC, Duan J, Yue TM (1998) Dynamic characteristics of gas jets from subsonic and supersonic nozzles for high pressure gas laser cutting. Opt Laser Technol 30(8):497–509
Man HC, Duan J, Yue TM (1997) Design and characteristic analysis of supersonic nozzles for high gas pressure laser cutting. J Mater Process Technol 63(1):217–222
Ermolaev GV, Kovalev OB, Zaitsev AV (2013) Parameterization of hybrid laser-assisted oxygen cutting of thick steel plates. Opt Laser Technol 47:95–101
White FM, Corfield I (2006) Viscous fluid flow, vol Vol.3. McGraw-Hill, New York
Wandera C, Kujanpaa V (2010) Characterization of the melt removal rate in laser cutting of thick-section stainless steel. J Laser Appl 22(2):62–70
Brandt AD, Settles GS (1997) Effect of nozzle orientation on the gas dynamics of inert-gas laser cutting of mild steel. J Laser Appl 9(6):269–277
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Zhang, C., Wen, P., Yuan, Y. et al. Evaluation and optimal design of supersonic nozzle for laser-assisted oxygen cutting of thick steel sections. Int J Adv Manuf Technol 86, 1243–1251 (2016). https://doi.org/10.1007/s00170-015-8268-7
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DOI: https://doi.org/10.1007/s00170-015-8268-7