00-02-07
0700 Morning routine back at
the hangar. …..
Gus described his usual method. He
normally embeds the bead in a plastic material
to ease handling. He then grinds off one
side several microns deep and examines the
surface under the SEM. He then grinds away
another couple of microns before re-examining
the surface. He continues this until the
bead is totally used up. It is a totally
destructive method. However, he cools the
grinding process by water so that there is no
heat damage – one plus for the system. I
suggested that the Focused Ion Beam system would
allow for numerous cuts, perhaps one-half or one
millimetre apart, and he questioned the time
involved as it is likely a very slow process,
and therefore very expensive. I asked him
if he could determine the elements present on
the ground surface, and he said that they do not
usually do this. I suggested that this was
something that CANMET could easily do with the
equipment that they have, providing a grid
pattern of the slices to show the elements
present and their location. He suggested
that it would be up to management to determine
if they want to spend the money. He also
questioned if it was within the mandate of the
TSB to conduct such tests to such an extent.
(It was later learned that FIB is not capable of
cutting through the beads, but is simply used to
slice out sections, as described in follow-up
emails from Dr. BROWN – added on 01-06-10)
|