Abstract
This study investigated the effect of
scanning speed and gas flow rate on surface finish
produced during the laser metal deposition process of
Ti6Al4V, an important aerospace alloy. In this work,
Nd-YAG laser was employed with coaxial powder
deposition nozzle attached to the end effector of a Kuka
robot. The laser power was maintained at 3.0 kW and
the powder flow rate at a value 2.88 g/min. The scanning
speed was varied between 0.01 and 0.05 m/s and the gas
flow rate was varied between 1 and 5 l/min. A total of ten
samples were produced and the surface roughness was
measured using the average of five measurements from
each sample. The microstructure was also studied with
optical microscope to relate it to the surface roughness.
The results showed that, the average surface finish
increased as the scanning speed was increased.
Conversely, as the gas flow rate was increased the
average surface roughness was reduced. In optimizing
the laser metal deposition process, the processing
parameters need to be optimized. The results from this
study will assist in choosing the right powder flow rate
and scanning speed especially in applications such as
repair and surface modification.