Effect of the Process Parameters on the Geometrical Defects of Ti-6Al-4V Hot Rolled Sheets Laser Beam Welded

Abstract:

Ti-6Al-4V is an alloy that is increasingly used in aeronautics due to its high mechanical properties coupled with the lightness. An effective technology used to manufacture titanium components with a reduced buy to fly ratio is the laser beam welding. Previous studies showed that the key factor that rules the mechanical properties and the fatigue life of the joint is its morphology. The aim of this paper was to investigate the influence of the main process parameters, such as welding speed and laser power, on the geometrical features of the joint, in terms of undercut, underfill, reinforcement and so on. 3.0 mm thick Ti-6Al-4V rolled sheets were welded in butt joint configuration by using a Nd-YAG laser source. The joint performances were studied in terms of weld morphology, microstructure and Vickers microhardness. Then, defects such as underfill and reinforcement, controlling the whole weld morphology, were observed, and the relationship between the occurrence, the entity of these defects and the process parameters was studied.

• Periodical: Key Engineering Materials (Volumes 651-653)
• Pages: 901-906
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.651-653.901
• Online since: July 2015
• Authors: Luca Boccarusso*, Giuseppe Arleo, Antonello Astarita, Franco Bernardo, Piero de Fazio, Massimo Durante, Giuseppe Giudice, Fabrizio Memola Capece Minutolo, Raffaele Sepe, Antonino Squillace
• Keywords: LBW, Titanium, Weld’s Morphology

References

[1] A. Squillace, et al. Effect of welding parameters on morphology and mechanical properties of Ti-6Al-4V laser beam welded butt joints. J. Mater. Process. Technol. 212, 2012: 427-436.

DOI: 10.1016/j.jmatprotec.2011.10.005

[2] E. Akman, et al. Laser welding of Ti6Al4V titanium alloys. J. Mater. Process. Technol. 209, 2009: 3705-3713.

[3] X. Cao et al. Effect of welding speed on butt joint quality of Ti-6Al-4V alloy welded using a high-power Nd: YAG laser. Optics and Laser in Engineering 47, 2009: 1231-1241.

DOI: 10.1016/j.optlaseng.2009.05.010

[4] P. Carlone, G.S. Palazzo, Characterization of TIG and FSW weldings in cast ZE41A magnesium alloy, J Mater Process Tech 215 (2015), 87-94.

DOI: 10.1016/j.jmatprotec.2014.07.026

[5] G. Lutjering, J.C. Williams. Titanium. Springer-Verlag, Heidelberg, Berlin. 2003: 177-194.

[6] J. Liu, et al. Joint strength of laser-welded titanium. Dent. Mater. 18, 2002: 143-148.

[7] P. Wanjara, et al. Ti-6Al-4V electron beam weld qualification using laser scanning confocal microscopy. Material Characterization. 54; 2005: 254-262.

DOI: 10.1016/j.matchar.2004.12.002

[8] M. Donachie, Titanium: A Technical Guide. ASM International, Metals Park, OH. 1989: 64-77.

[9] T. Ahmed, et al. Phase transformation during cooling in α+β titanium alloys. Mater. Sci. and Engi. A243, 1998: 206-211.

[10] W. Shaogang, et al. Investigation on the microstructure and mechanical properties of Ti-6Al-4V alloy joints with electron beam welding. Mater. Des. 36, 2012: 663-670.

DOI: 10.1016/j.matdes.2011.11.068

[11] K. Abhay, et al. Failure analysis of a Ti-6Al-4V gas bottle. Eng. Fail. Anal. 13, 2006: 843-856.

DOI: 10.1016/j.engfailanal.2005.02.011