Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 33093
Metallographic Analysis of Laser and Mechanically Formed HSLA Steel
Authors: L.C. Kgomari, R.K.K.Mbaya
Abstract:
This research was conducted to develop a correlation between microstructure of HSLA steel and the mechanical properties that occur as a result of both laser and mechanical forming processes of the metal. The technique of forming flat metals by applying laser beams is a relatively new concept in the manufacturing industry. However, the effects of laser energy on the stability of metal alloy phases have not yet been elucidated in terms of phase transformations and microhardness. In this work, CO2 laser source was used to irradiate the surface of a flat metal then the microstructure and microhardness of the metal were studied on the formed specimen. The extent to which the microstructure changed depended on the heat inputs of up to 1000 J/cm2 with cooling rates of about 4.8E+02 K/s. Experimental results revealed that the irradiated surface of a HSLA steel had transformed to austenitic structure during the heating process.Keywords: Laser, Forming, Microstructure
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1062120
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1811References:
[1] H. Arnet & F. Vollersen. "Extending laser bending for the generation of convex shapes", J.of Eng. Manufacture (209), 1995, pg 433-441.
[2] T. Hinnige, S. Holzer, F. Vollersen & M. Geiger "The accuracy of laser bending, Material Process Technology" (70) 1997 pg 351-355.
[3] K.C. Chan et al. Laser bending of thin stainless steel sheets, Journal of laser applications, laser Institute of America, 32-40.
[4] J. Magee, K. G. Watkins, & W. M. Steen, "Advances in laser forming", Laser Applications, (6) 10. 1998.
[5] W. Li & Y.L. Yoa, Effects of strain rate in laser forming. Proceedings of the International Conference of lasers and Electro-Optics, Orlando 1999, pg 102-111.
[6] L. Fratini & F. Micari, "The influence of the technological and geometrical parameters in laser bending process", in Proceedings of the International Symposium for electromachining, Lausanne, Switzerland, 1995, pg 753 - 761.
[7] J. Lawrence, M.J.J. Schmidt & L. Li, "The forming of mild steel plates with 2.5kW high power diode laser". J. of Machine tools & manufacture, vol. 41, 2001, pg 967-977.
[8] G. Thomson & M. Pridham, Material property changes associated with laser forming of mild steel components, J. of Mat. Proc. Technology 118, 2001 pg 40-44.
[9] P.J. McGrath & C.J. Hughes, Experimental Fatigue Performance of Laser Formed Components, J of Optical and lasers in engineering, submitted 2005.
[10] Bruder, E., Bohn, T. & M├╝ller, C. (2008). Properties of UFG HSLA steel profiles produced by linear flow splitting. Material Science Forum, 584-586: 661-666.
[11] K. Hulka, "The role of niobium in low carbon bainatic HSLA steel," www.msm.com.ac.uk/phase_trans/2005/link/10pdf. 2005