Silver Nitrate Inspection
Silver Nitrate (AgNO3) Inspection is a chemical test method used by QMS technicians to identify selective phase corrosion in NAB castings subjected to saltwater. Selective phase corrosion or SPC is a form of corrosion where the aluminium in the NAB is leached out of the material and replaced with a porous copper matrix. The copper can mask any visible signs of corrosion or pitting within the material even though the mechanical properties have been greatly reduced. Silver Nitrate, which is a clear solution, reacts with the free copper on the areas affected by SPC to form a visible black indication. These areas can be marked and ground out to assess the depth of damage to the item. Primary Applications:
- Inspection of NAB castings subjected to salt water.