The work is concerned with the investigation of the hot corrosion of
a typical nickel-based superalloy Nimonic 105. The literature published
up to the start of the present work has been reviewed to highlight
areas in which research on this particular alloy should be focussed.
To obtain hot corrosion under the carefully controlled conditions
so essential for mechanistic diagnosis samples of Nimonic 105 have been exposed to pure Na2so4, Na2so4 with NaCl additions and pure
NaCl at 1173K in flowing oxygen using a controlled potentiometric
partial immersion crucible technique. After exposure the specimens
were fully examined using metallography, electron probe microanalysis,
scanning electronmicroscopy, X-ray diffraction and X-ray spectrometry to establish the morphological and scaling characteristics of
corrosion. In addition a number of diagnostic experiments were
devised to elucidate various points which emerged during the course
of the work. [Continues.]
A doctoral thesis submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy at Loughborough University.