Brass is susceptible tostress corrosion cracking, especially fromammoniaor substances containing or releasing ammonia. The problem is sometimes known asseason crackingafter it was first discovered in brasscartridge casesused forrifle ammunitionduring the 1920s in theIndian Army. The problem was caused by highresidual stressesfrom cold forming of the cases during manufacture, together with chemical attack from traces of ammonia in the atmosphere. The cartridges were stored in stables and the ammonia concentration rose during the hot summer months, thus initiating brittle cracks. The problem was resolved byannealingthe cases, and storing the cartridges elsewhere.

The most common example is selective leaching of zinc frombrassalloys containing more than 15%zinc(dezincification) in presence of oxygen and moisture, e.g. from brass taps inchlorine-containing water. It is believed that both copper and zinc gradually dissolved out simultaneously and copper precipitates back from the solution. The material remaining is a copper-rich sponge with poor mechanical properties, and color changed from yellow to red. Dezincification can be caused by water containingsulfur,carbon dioxideandoxygen. Stagnant or low velocity waters tend to promote dezincification. To combat this,arsenicortincan be added to brass, orgunmetalcan be used instead.Dezincification resistant brass(DZR), also known asBrass C352,[1]is an alloy used to make pipe fittings for use withpotable water. Plumbing fittings that are resistant to dezincification are appropriately marked, with the letters "CR" (Corrosion Resistant) or DZR (dezincification resistant) in the UK, and the letters "DR" (dezincification resistant) in Australia.