Stress Corrosion Cracking of Manganese Bronze in Water

Continuous and centrifugal cast manganese bronze parts (C86300) experienced intergranular cracking in as few as 24 h after being stored outside. C-ring tests according to ASTM G38 were conducted to assess the material’s susceptibility to stress corrosion cracking (SCC) susceptibility and found that water was the most likely agent. The failure mechanism has been identified as intergranular SCC due to a combination of residual stress from a rough machining operation and water from rain or dew. To prevent cracking, a stress relief heat treatment immediately after the rough machining operation is recommended.