The influence of three different types of stirring: mechanical, ultrasonic
and a combination of both, on the mass transport coefficient and on the cha
racteristics of the deposit of lead on copper electrodes has been studied.
The results obtained show that ultrasounds always provide higher mass trans
port rates than mechanical stirring. The best deposition characteristics ar
e obtained at 35 degrees C using a combination of ultrasound and mechanical
stirring. Normally, ultrasounds increase the quality of the deposit by dec
reasing the number and size of dendrites. However, the sonication time has
a strong influence on the adherence of the deposits. Thus, for long sonicat
ion times, part of the lead deposit detaches itself from the surface, givin
g deposits of very poor quality. A preliminary study of lead deposition on
three-dimensional copper foam electrodes was made and similar results were
obtained. With mechanical stirring, the interior of the foam was not coated
with lead while when combined stirring was used, better results were obtai
ned. However, for long sonication times the mechanical stability of copper
foams is strongly decreased and the electrode is destroyed.