Optimization of Bead Geometry in CO₂ Laser Welding of Ti 6Al 4V Using Response Surface Methodology

Ali Khorram, Majid Ghoreishi, Mohammad Reza Soleymani Yazdi, Mahmood Moradi

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DOI: 10.4236/eng.2011.37084                

Abstract

In the presented study, the laser butt-welding of Ti 6Al 4V is investigated using 2.2 kw CO₂ laser. Ti 6Al 4V alloy has widespread application in various fields of industries including the medical, nuclear and aerospace. In this study, Response Surface Methodology (RSM) is employed to establish the design of experiments and to optimize the bead geometry. The relationships between the input laser-welding parameters (i.e. laser power, welding speed and focal point position) and the process responses (i.e. welded zone width, heat affected zone width, welded zone area, heat affected zone area and penetration depth) are investigated. The multi-response optimizations are used to optimize the welding process. The optimum welding conditions are identified in order to increase the productivity and minimize the total operating cost. The validation results demonstrate that the developed models are accurate with low percentages of error (less than 12.5%).

Keywords

Laser Welding, Response Surface Method (RSM), Optimization, Ti 6Al 4V

Conflicts of Interest

The authors declare no conflicts of interest.

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