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The
task was to position a glass prism in an optical lens system
in order to deflect a laser beam. A mounting unit needed to be
designed to absorb as little light as possible. Therefore it
needed to be designed as slim as possible and at the same time
as stable as possible.
Since the instrument holds a glass prism and must work
accurately under conditions from -20oC to +50oC a Nickel Iron
alloy had to be chosen for its coefficient of expansion. 
Once the material had been specified it became evident that
only MIM could cost effectively produce a part with such thin
walls and intricate shape, but even for MIM the part seemed
critical.
All cross sections are between 0.5 and 0.7 mm thin and the
material must fill over long distances. The diameter of the
part is 43mm. Distortion and uneven shrinkage were the key
problems that needed to be overcome.
During development Parmaco pushed the envelope of MIM by fine
tuning the injection mould, the feedstock and the sintering
procedures. Today this part is a masterpiece of MIM
capabilities and gives cost savings over a machined part (the
only alternative production method) of more than 95%.
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