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 respectively. 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 on palladium. 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.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:309633 |
| Date | January 1935 |
| Creators | Sun, Ching-Hwa |
| Publisher | Imperial College London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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