Struers Tenupol-3 Mode D'emploi page 25

Re 1:
Re 2:
Tenupol-3
Instruction Manual
In Tenupol-3 polishing, the polishing defects may be divided into the
following classes:
1. Defective polishing, i.e. wrong polishing conditions, so that a mirror-like
finish is absent on one or both sides of the specimen. Pitting may be
present.
2. Polishing takes place, but no thin area is present at the edge of the
hole.
try to alter the electrical conditions. Perhaps the voltage was too low to
reach the polishing range. Pittings may arise if the current was too high. A
lowering of the temperature may make the polishing less sensitive to
voltage changes. The flow rate should be altered. A too high flow rate may
break up the polishing layer, which may be the cause of one side of the
specimen not being polished. A slower flow may allow a polishing layer to
be built up.
If nothing helps it can be concluded that the material in question cannot be
polished by the electrolyte and another electrolyte should be tried.
the hole may have grown too large, so that the thin foil first formed has
disappeared. Just like electropolishing will attack the tops of the aspirates of
the surface, it will attack the edge of the hole as being an asperity.
Especially when the jet effect is strong it is very important to stop the
process while the hole is small.
Adjustment of the flow rate may be helpful. A vigorous jet may attack a too
small area. Another electrical current density should also be tried.
Try increasing the photo sensitivity by turning the knob (fig. 10.10)
clockwise.
Sometimes a lower temperature will give a better profile around the hole,
possibly on account of a change of viscosity.
If nothing helps it is probable that the electrolyte is not suitable for thinning
the material in question, although it will electropolish it. Try another
electrolyte.
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