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
- A286 set screw features and benefits
Screws 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 set screws with high levels of strength from room temperature up to about 1300°F (700°C).
A-286 set screws 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 set screws 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
A286 set screws are unique in that they have no screw head, meaning that they have no protruding part past the threaded shaft. They are thread only and are available with a socket or slotted driver insert at one end. Set screws are used to secure an object within or against another object. Typically they secure a rotating part such as a gear or shaft. A286 set screws are driven through a threaded hole in the rotating part until it is tight against the inner object, preventing from moving relative to the outer object. Set screws are available with various points depending on the application.
This is the most commonly used set screw and is identified by a cup-shaped indentation on one end. A286 cup points are typically used for a quick, semi-permanent or permanent applications where it is acceptable to cut the cup point edge of the screw.
A cone point is easily identifiable by its sharp cone-shaped point – just like an ice cream cone. A286 cone point set screws deliver the strongest clamping force due to the deep penetration of the point. As a result they are used for permanent assembly.
The cheapest and simplest of the set screw point styles, this screw has a flat surface on the bottom of the screw. This type is used when you need the ability to frequently change parts and require minimal shaft deformation.
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