Hastelloy B3 is a nickel-molybdenum alloy with excellent resistance to pitting, corrosion, and stress-corrosion cracking plus, thermal stability superior to that of alloy B2. In addition, this nickel steel alloy has great resistance to knife-line and heat–affected zone attack. Alloy B3 also withstands sulfuric, acetic, formic and phosphoric acids, and other non-oxidizing media. Furthermore, this nickel alloy has excellent resistance to hydrochloric acid at all concentrations and temperatures. Hastelloy B3’s distinguishing feature is its ability to maintain excellent ductility during transient exposures to intermediate temperatures. Such exposures are routinely experienced during heat treatments associated with fabrication.
Alloy B-3 has poor corrosion resistance to oxidizing environments, therefore, it is not recommended for use in oxidizing media or in the presence of ferric or cupric salts because they may cause rapid premature corrosion failure. These salts may develop when hydrochloric acid comes in contact with iron and copper. Therefore, if this nickel steel alloy is used in conjunction with iron or copper piping in a system containing hydrochloric acid, the presence of these salts could cause the alloy to fail prematurely.
Advantages of Hastelloy B3
Chemical composition of Hastelloy B3(N10675)
Elements | Ni | Mo | Fe | C | Co | Cr | Mn | Si | Ti | W | Al | Cu |
Weight(%) | 65.0 min | 28.5 | 1.5 | 0.01 max | 3.0 max | 1.5 | 3.0 max | 0.1 max | 0.2 max | 3.0 max | 0.50 max | 0.20 max |