The structure of electrodeposited metals.
The work was suggested by Prof, G. I, Finch and carried
out under his supervision in his laboratory at the Imperial
College of Science., London, It was undertaken to study the
structure of the first thin layers of electrodeposited metals
and their properties by means of electron diffraction with a
view to obtaining some light on the mechanism of electrodeposition.
The thesis is divided into the following parts:
lo An electrochemical method for making transmission films
for electron diffraction is described, Transmission-films of
14 metals were made, namely, Cu, Ag, Au, Fe, Co, Ni, As, Sb,
Bi, Pt, Sn, Cr. W and Se,
2, The lattice dimensions of platinum electrodeposited on
silver, gold and zinc on coppers nickel and chromium on gold,
iron on nickel, copper and nickel on platinum and copper and
iron on palladium were found to be normal, whilst platinum
displaced by copper and silver formed alloys with the substrates
3. Deposits of iron, nickel, coppers brass, gold, tin and
platinum show preferred orientations.
4, Double scattering of electrons occurred with composite
films of copper and nickel on platinum respectively and copper
5. The effect of substrates on the structure of the deposits
was studied with copper, gold, iron, nickel, tin, platinum,
silvers palladium, zinc, brass, bismuth, arsenic and chromium.
The grain size of chromium films was found to have changed
with the substrates. The orientation relation for the crystlline
substrates studied show that the correspondingly dense
planes of the deposit and the substrate are parallel. An
amorphous arsenic substrate, however, exerted no effect on
the orientation of a deposit, A zinc film was found to have
dissolved in the polished layer of a copper surface.
6, Nickel, iron, copper and gold films were anodically oxidised
and electron diffraction patterns for passive nickel,
iron and gold were obtained.