Obviously, I'm unworthy and incompetent (dangerous) as a metallurgist. Just
hang around them too much. Also obvious, I have way too much time on my
hands before starting my new contract (DFM and safety engineer for munitions
and fuse making company - eehaw!). Safety in a bomb factory? Sure looking
forward to this one.

According to the new world soldering technology and technologists,
intermetallics must form for a solder joint to be effected. This revelation
has occurred over the past twenty or so years. Before that, Manko dictated
that solder joints may be formed by joing to metal surfaces with a solder
medium without requiring diffusion or intermetallic formation. I rather
still like this as I work with surface scientists from time to time.

Surface scientists regard a surface as being an objects area having no
depth. At the same time, to analyze surface defects or quality conformity,
they do not regard a surface as having been reached until a specified number
of angstroms has been probed. An angstrom is a unit of length equal to
one-ten-millionth of a millimeter, used for atomic measurements and
wavelengths. I like what they say concerning intermetallic formations never
reaching "depth" though, when they do, IMC thickness may be too much to
promote reliable solder joints.

What Manko was describing, I believe, was a condition wherein atomic
mono-layers comprised the surface and that the solder "wetting" process was
a function of not reaching farther than a surface scientist's definition of
it. I just pose this to get a little something shaking during such trying
times made up of much boredom punctuated with shear terror for some in times
of terrible proportions.

Earl

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