A variety of different preparation techniques have been used in order
to identify the experimental conditions under which interface phases a
re formed in the near-alpha alloy, IMI 834. In particular, a Ni plated
surface examined in cross-section in the TEM produced a gradation in
hydrogen content from high at the surface to low levels in the bulk. T
wo transformation products have been identified, one was a monolithic
fee phase with a lattice parameter of a = 0.434 +/- 0.004 nm, which fo
rms along alpha-platelet boundaries, and the second was an acicular fe
ature which formed between alpha-platelet boundaries which was tentati
vely identified as an hcp phase twin related to the alpha-titanium. Th
e monolithic interface phase was found to form at both low and high hy
drogen levels while the alpha twins were only seen at high hydrogen co
ntents. In all cases, the transformations were shown to be artefactual
and induced solely by hydrogen absorption. No evidence of mechanical
strain induced interface phase formation was found. In conflict with t
he literature, the monolithic fcc phase was found to occur during ion-
beam milling and was attributed to water contamination of the milling
gas. Formation of the interface phase was suppressed by electropolishi
ng at temperatures less than or equal to - 50 degrees C.