Admiralty Brass and chlorides

[eml]

Does anyone know the effects of chlorides on admiralty brass ?

 

[aberta]

What are the chloride levels?

 

[TVP]

Can you provide additional details on the type of chlorides (sodium, calcium, etc.), temperature, pH, etc.? Also, what type of admiralty brass are you using (composition, product form, heat treatment)? Chlorides produce de-zincification in high Zn copper alloys, but this effect is retarded by additions of Sn. Inhibited admiralty Cu may also contain P, Ar, or Sb which further improves resistance to de-zincification. In general, this type of alloy is categorized as having "fair" resistance to CaCl[sub]2[/sub] and "poor" resistance to NaCl.

 

[Metalguy]

The inhibited Adm. brasses may be more res. to dezinc., but they become MORE susceptible to SCC.

Regular Adm. brass does *fairly well* out on the clean high seas (well, at least they used to be clean many years ago), but in semi-polluted harbors they fail quickly (sulfides).

The Cu-Ni's do much better.