Crampons take immense punishment from rock and ice under normal use. Maintaining crampons and checking them regularly is therefore of vital importance. Users that neglect crampon maintenance are liable to find themselves halfway up an ice sheet with broken equipment.
Crampon maintenance need not be overly laborious. Be sure to inspect your crampons after each usage to check for damage, missing parts, or signs of fatigue. Repair or replace any worn parts and remember that crampons are not the sort of equipment you want to leave to chance. If it looks worn, replace it! Always clear your crampons of loose dirt and material before storing them careful until next time. If you are storing them for the season, cover them with a light oil or WD-40.
To maintain their performance you need to keep the points of your crampons sharp and straight. Only use a hand file to sharpen the points of your crampons; a grinding wheel will overheat the metal. Carefully straighten any bent points if possible.
Even fastidiously maintained crampons can break or fail at just the wrong time. For this reason, it is a good idea to carry a selection of spare parts and the tools necessary to fit them. Consider carrying extra bolts/nuts, straps, bails, etc. Some long cable-ties and duct tape are also excellent for make-do repairs.
If you have been performing your crampon maintenance, it is likely that your points will be nice and sharp. You should always stow your crampons in a padded crampon case or, at the very least, use rubber point covers. Exposed points can damage your bag, ropes, clothes or flesh.