Authors: N.I.S. Hussein, I.R. Pashby, D.G. McCartney
Addresses: School of Mechanical, Materials and Manufacturing Engineering, University of Nottingham, Nottingham NG7 2RD, UK. ' School of Mechanical, Materials and Manufacturing Engineering, University of Nottingham, Nottingham NG7 2RD, UK. ' School of Mechanical, Materials and Manufacturing Engineering, University of Nottingham, Nottingham NG7 2RD, UK
Abstract: Laser and electric arc are widely known heat sources used in the joining of metals. High Power Diode Laser (HPDL) and Tungsten Inert Gas (TIG) were used in this investigation. As they are additive welding processes with additional material supplied by filler wire the processes can be viewed as a metal deposition technique. If used with an appropriate manipulation system it can be used to build three-dimensional metallic parts for rapid prototyping or rapid manufacture. Complex components for use in aero engine systems can have very long manufacturing lead times when made by conventional processes, this is a severe hindrance during the product development cycle and the ability to use layer-by-layer methods of metal deposition would be very useful. The properties of many aerospace alloys are very sensitive to the production methods used so the use of alternative methods of manufacture has to be carefully considered and the property/process relationship understood. In this preliminary study, change of process parameters throughout building various layers of Waspaloy deposit was observed and the effect of metallurgical and mechanical properties of the deposits were analysed. The results suggest that the layer-by-layer deposition causes dynamic changes in the microstructure and geometry of the substrate and the previous deposited layer mainly due to heat transfer. This is more crucial when depositing Waspaloy because the temperature gradient during the deposition process affects the growth of gamma prime (γ′) precipitates and carbide particles which has an important impact on the mechanical properties of the material. Future work on process modelling will be carried out.
Keywords: HPDL welding; high power diode laser; TIG welding; tungsten inert gas; direct metal deposition; Waspaloy deposition; microhardness; laser welding; arc welding; process parameters; microstructure; heat transfer.
International Journal of Manufacturing Technology and Management, 2009 Vol.17 No.4, pp.419 - 425
Published online: 22 Mar 2009 *Full-text access for editors Access for subscribers Purchase this article Comment on this article