Citation:
Investigation of the benefits of plasma deposition for the additive layer
manufacture of Ti-6Al-4V. Journal of Materials Processing Technology, Volume 212, Issue 6, June 2012, Pages 1377-1386
Abstract:
With increasing emphasis on sustainability, Additive Layer Manufacturing (ALM)
offers significant advantages in terms of reduced buy-to-fly ratios and improved
design flexibility. Plasma Wire Deposition is a novel ALM technique in which
plasma welding and wire feeding are combined. In the present work, a working
envelope for the process using Ti–6Al–4V was developed, and regression models
were calculated for Total Wall Width, Effective Wall Width and Layer Height. The
Plasma Wire Deposition process is able to produce straight walls of widths up to
17.4 mm giving a maximum effective wall width after machining of 15.9 mm, which
is considerably wider than competing processes. In addition, for Ti–6Al–4V the
deposition efficiency averages 93% and the maximum deposition rate is 1.8 kg/h.
Coarse columnar grains ofβphase grew from the base during deposition, which
transformed into a Widmanstätten structure ofαlamellae on cooling. Bands were
identified in the deposits, which had a repetitive basket-weave microstructure
that varied in size. The strength measured by micro-indentation hardness of 387
HV on average is as much as 12% higher than the substrate. These preliminary
results indicate that Plasma Wire Deposition is likely to be a suitable process
for the ALM of large aerospace