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Laser beam forming is a novel technique developed for the joining of metallic components. In this study, an overview of the laser beam forming process, areas of application, the basic mechanisms of the laser beam forming process, some recent research studies and the need to focus more research effort on improving the laser-material interaction of laser beam forming of titanium and its alloys are presented., {"references":["M. J. Dutta, A. K. Nath, I. Manna, Studies on Laser bending of stainless\nsteel. Material Science and Engineering A, Vol. 385, 2004, pp. 113 -122.","Metal bending process, 2012, [Online]. Available:\nhttp://www.efunda.com/processes/metal_processing/bending.cfm\n(Accessed 10th July, 2012).","S. M. Knupfer, A. J. Moore, The effects of laser forming on the\nmechanical and metallurgical properties of low carbon steel and aluminium alloy samples. Materials Science and Engineering A, 2008\ndoi:10.1016/j.msea.2010.03.069.","M. Marya, G. R. Edwards, An analytical model for the optimization of\nthe laser bending of titanium Ti-6Al-2Sn-4Zr-2Mo. Journal of Materials\nProcessing Technology, 2002, Issue 124.","M. Geiger, F. Vollertsen, G. Deinzer, Flexible Straightening of car body\nshells by laser forming, In: International Congress and Exposition, Detroit, MI, USA: 1993 Published by SAE, Warrendale, PA, USA.","M. Geiger, H. Arnet, F. Vollertsen, Laser forming, in: Proceedings of the\nLANE, 1994, p. 81-92.","D. F. Walczyk, S. Vittal, Bending of Titanium Sheet Using Laser\nForming. New York: Journal of Manufacturing Processes, Issue 4, Vol. 2. 2000.","M. S. Che Jamil, M. A. Sheikh, L. Li, A Numerical Study of the\nTemperature Gradient Mechanism in Laser Forming Using Different\nLaser Beam Geometries. Pulau Pinang: OCP Science imprint, a member\nof the Old City Publishing Group, 2011, Vol. 22.","D. Chen, S. Wu, M. Li, Deformation behaviours of laser curve bending\nof sheet metals. Xi-an: Journal of Materials Processing Technology, Vol.\n148, 2001.\n[10] S. P. Bartkowiak, Laser forming of thin metal components for 2D and\n3D applications using a high beam quality, low power Nd: YAG Laser and rapid scanning optics. Bremen: International Workshop on Thermal Forming, 2005.\n[11] E. Kannatey-Asibu, Principle of laser materials processing. John Wiley\n& sons, Inc., New York, N.Y., 2009.\n[12] G. Dearden, S. P. Edwardson, Some recent development in 2 and 3\ndimensional laser forming for macro and micro applications. Journal of\nOptics A: pure and Applied Optics Vol. 5, 2003, pp. 8-15.\n[13] L. Lawrence, M. J. J. Schmidt, L. Li, The forming of mild steel plates\nwith a 2.5 kW high power diode laser. International Journal of Machine\nTools and Manufacture Vol. 41, 2001, pp. 967-977.\n[14] F. R. Liu, K. C. Chan, C. Y. Tang, Numerical simulation of laser\nforming of aluminium matrix composites with different volume fractions\nof reinforcement. Materials Science and Engineering a Vol. 458, 2007,\npp. 48-57.\n[15] S. A. Akinlabi, E. T. Akinlabi, M. Shukla, Effect of laser beam forming\non microstructure and mechanical properties of AISI 1008 steel\"\nPresented at ASME McMat 2011, May 30 - June 2, 2011 in Chicago, USA.\n[16] S. A. Akinlabi, T. Marwala, M. Shukla, E. T. Akinlabi, Laser beam\nforming of 3 mm steel plate and the evolving properties. International\nConference on Manufacturing Engineering ICME 2011 Venice, Italy, 28\n- 30th November 2011, organized by World Academy of Science, Engineering and Technology on Materials and Manufacturing (WASET).\n[17] C. Thompson, M. Pridham, Material property changes associated with\nlaser forming of mild steel component. J Meter Process Technology,\nVol. 118, 2001, pp. 40-44.\n[18] L. J. Yang, J. Tang, M. L. Wang, Y. Wang, Y. B. Chen, Surface\ncharacteristic of stainless steel after pulsed laser forming. Applied\nSurface science Vol. 256, 2010, pp. 7018- 7026.\n[19] Y. Shi, Z. Yao, H. Shen, J. Hu, Research on the mechanisms of laser\nforming for the metal plates. International Journal of Machine Tools and\nManufacture Vol. 46, 2006, pp. 1689-1697.\n[20] S. P. Edwardson, P. French, K. G. Dearden, K. G. Watkins, W. J.\nCantwell. Laser forming of fibre metal laminates. Lasers in Engineering.\nVol. 15, pp. 233-255.\n[21] F. Vollertsen, Mechanisms and models for laser forming. Laser assisted\nnet shape engineering, in: Proceedings of the LANE, vol. 1, Meisenbach\nBamberg, 1994, pp. 345-360.\n[22] W Li, Y. L. Yao. Laser bending of tubes: Mechanisms, Analysis and\nPrediction. Transaction of the ASME, Vol. 123, November 2001.\n[23] F. Vollertsen, Laser forming, Mechanisms, Models, Applications in LFT\nErlangen monograph, 1995.\n[24] M. Geiger, F. Vollertsen, The Mechanisms of Laser Forming, CIRP\nANNALS Vol. 42, 1993, pp. 301 - 304.\n[25] J. Magee, K. G. Watkins, W. M. Steen, Advances in laser forming.\nJournal of laser Application Vol. 10, 1996, pp. 235-256.\n[26] S. A. Akinlabi, M. Shukla, E. T. Akinlabi, T. Marwala \"Laser beam in\nforming application\" Laser in Manufacturing by ISTE/Wiley Publishing\nhouse.\n[27] J. Kim, B. M. Son, B. S. Kang, H. J. Park, Comparison stamping and\nhydro-mechanical forming process for an automobile fuel tank using\nfinite element method. Journal of Material Processing Technology Vol.\n153-154, 2004, pp. 550-557.\n[28] J. Magee, J. Sidhu, R. L Cooke. A prototype laser forming system,\nOptics and Lasers in Engineering, Vol. 34, 2000, pp. 339-353.\n[29] D. A. Hollander, Walter M. V, T. Wittz, R. Sellei. Structural, mechanical\nand invitro characterisation of individually structured Ti-6Al-4V\nproduced by direct laser forming. Journal of Biomaterials, Vol. 27, 2006,\npp. 955-963.\n[30] D. J. Chen, S. C. Wu, M. Q. Studies on laser forming of Ti-6Al-4V alloy\nsheet. Journal of Materials Processing Technology, Vol. 152, 2004, pp. 62-65."]}

The study of effect of laser scanning speed on material efficiency in Ti6Al4V application is very important because unspent powder is not reusable because of high temperature oxygen pick-up and contamination. This study carried out an extensive study on the effect of scanning speed on material efficiency by varying the speed between 0.01 to 0.1m/sec. The samples are wire brushed and cleaned with acetone after each deposition to remove un-melted particles from the surface of the deposit. The substrate is weighed before and after deposition. A formula was developed to calculate the material efficiency and the scanning speed was compared with the powder efficiency obtained. The results are presented and discussed. The study revealed that the optimum scanning speed exists for this study at 0.01m/sec, above and below which the powder efficiency will drop, {"references":["M.N. Ahsana, A.J. Pinkerton, R.J. Moatb, and J. Shackleton, A comparative study of laser direct metal deposition characteristics using gas and plasma-atomized Ti-6Al-4V powders, Materials\nScience and Engineering A 528 (2011) 7648- 7657.","A. R. Machado, and J. Wallbank, Machining of Titanium and Its Alloys:\nA Review, Proceedings of the Institution of\nMechanical Engineers Part B: Management and Engineering\nManufacture, Vol. 204, No. 11, 2005, pp. 53-60.","C.W. Fink, An overview of additive manufacturing. Part II, AMMTIAC\nQuarterly. 2009, 4(3):7 - 10.","DT. Pham, C. Ji and CC. Dimov, Layered manufacturing technologies,\nProc. of the International Conf. on New Forming Tech., ICNFT, Sept. 2004, Harbin, China, pp. 317-324.","J. Allen, An Investigation into the Comparative Costs of Additive Manufacture vs. Machine from Solid for Aero Engine Parts. In Cost Effective Manufacture via Net-Shape Processing,\nMeeting Proceedings RTO-MP-AVT-139, Paper 17, 2006, pp. 1 - 10.","P. Bergan, Implementation of laser repair processes for navy aluminum\ncomponents, Proceeding of Diminishing\nManufacturing Sources and Material Shortages Conference\n(DMSMS), 2000, available at:\nhttp://smaplab.ri.uah.edu/Smaptest/Conferences/\ndmsms2K/papers/decamp.pdf, accessed on 13th July 2012.","W. Zhou, and K.G. Chew, Effect of welding on impact toughness of butt-joints in a titanium alloy, Materials Science and Engineering A347, 2003 ,pp.180-185.","A.J. Pinkerton, and L. Li, (2004). Multiple-layer cladding of stainless\nsteel using a high- powered diode laser: an experimental\ninvestigation of the process.","W.M. Steen, (2003). Laser Material Processing, Springer-Verlag."]}

Laser Metal Deposition (LMD) is an additive manufacturing process with capabilities that include: producing new part directly from 3 Dimensional Computer Aided Design (3D CAD) model, building new part on the existing old component and repairing an existing high valued component parts that would have been discarded in the past. With all these capabilities and its advantages over other additive manufacturing techniques, the underlying physics of the LMD process is yet to be fully understood probably because of high interaction between the processing parameters and studying many parameters at the same time makes it further complex to understand. In this study, the effect of laser power and powder flow rate on physical properties (deposition height and deposition width), metallurgical property (microstructure) and mechanical (microhardness) properties on laser deposited most widely used aerospace alloy are studied. Also, because the Ti6Al4V is very expensive, and LMD is capable of reducing buy-to-fly ratio of aerospace parts, the material utilization efficiency is also studied. Four sets of experiments were performed and repeated to establish repeatability using laser power of 1.8 kW and 3.0 kW, powder flow rate of 2.88 g/min and 5.67 g/min, and keeping the gas flow rate and scanning speed constant at 2 l/min and 0.005 m/s respectively. The deposition height / width are found to increase with increase in laser power and increase in powder flow rate. The material utilization is favoured by higher power while higher powder flow rate reduces material utilization. The results are presented and fully discussed.