Zeron Fastners
ZERON 100 SA (Solution Annealed) Specification
Product Overview: Manufacturing & Economy
ZERON 100 SA (Solution Annealed) represents the standard, readily available form of ZERON 100 Super Duplex (UNS S32760). Although it has a lower inherent yield and tensile strength compared to the Fastener Grade (FG), it offers a significant advantage in manufacturing economy for certain fastener types.
Headed bolts and specialized fasteners can be produced more cheaply in the Solution Annealed condition because they can be produced through forging followed by solution annealing. This contrasts with the FG grade, which must be machined entirely from strain-hardened bar.
SA Role in Anti-Galling & Nut Manufacturing
Galling (cold welding) is minimized when coupling two surfaces of differing hardness. For this reason, ZERON 100 SA material is typically used for manufacturing nuts.
| Fastener Component | ZERON 100 Grade Used | Advantage |
|---|---|---|
| Bolts (FG grade) | ZERON 100 FG (Cold Worked) | Maximum Tensile Strength |
| Nuts | ZERON 100 SA (Solution Annealed) | Lower Hardness (approx. 50HV less than FG) |
Pairing the lower hardness ZERON 100 SA nuts with the higher hardness ZERON 100 FG bolts minimizes the risk of galling in high-torque flange connections, ensuring ease of dismantling.
Applications
ZERON 100 SA is often specified for pipework systems and flanges handling corrosive fluids where cost-effective, easily forged, corrosion-resistant fasteners are required, and where the extreme strength of the FG grade isn't mandatory. The grade maintains the alloy's hallmark high corrosion resistance (including immunity to chloride stress corrosion cracking).
