A Fe-Ni-Cr alloy with excellent high temperature oxidation resistance
- Good material for high temperature oxidation resistance
- Maintains high strength at elevated temperatures
- A286 Chemistry, specs, and heat treatments
Nuts and lock nuts made from A-286 are known for their high strength, creep resistance and oxidation resistance at elevated temperatures. This iron-nickel-chromium alloy (once age-hardened) provides A-286 nuts with high levels of strength from room temperature up to about 1300°F (700°C).
A-286 nuts are mildly corrosion resistant. While they should not be used for strong acid environments, they provide excellent oxidation resistance up to 1300°F (700°C) in conditions that would typically be found in high temperature exhaust streams.
Because of these properties, A-286 nuts are often found in high temperature engine, manifold, exhaust and turbine applications as well as off-shore oil & gas applications.
Resources: A-286 Torque Specs
A-286 Heat Treatments: There are several heat treatment combinations for A-286 all with slight variations in performance. They can be specified via an AMS number or a 660 Class: A, B, C or D, with most common specified as class A or D. The A-286 grades A, B and C all have the same min tensile strength and min yield strength of 130ksi and 85ksi respectively. However grade D is significantly better yield with a min tensile of 130ksi and a min yield of 105ksi.
By AMS numbers, the most common for A-286 is AMS 5737 (same as Grade A) and then AMS 5732 (same as Grade B).
A-286 Specifications: AMS 5525, AMS 5732, AMS 5737, AMS 5804, EN 1.4980, GE B50T1181, GE B50T12, GE B50T81, UNS S66286, Werkstoff 1.4980