A286 Stainless Steel
Iron-base superalloy, for bolts and heat
Typical values for the temper in the title
A286 is an austenitic stainless steel hardened by precipitation, and is therefore considered an iron-base superalloy. Nickel (about 25%) keeps a non-magnetic austenitic structure, and titanium forms strengthening precipitates on aging.
It keeps strength and oxidation resistance up to about 700 °C, and is cheaper than nickel alloys. Its main use is bolts and fasteners in aerospace and jet engines (per ASTM A453 Grade 660 and AMS specifications), and also turbine parts and hot structures.
Mechanical and physical properties
| Property | Value | Note |
|---|---|---|
| Tensile strength Rm | ≥895 MPa (A453 Gr. 660) | |
| Yield strength Rp0.2 | ≥585 MPa (A453 Gr. 660) | |
| Elongation A | ≥15% | |
| Modulus of elasticity E | 201 GPa | |
| Density ρ | 7.94 g/cm³ | |
| Machinability | 35% | relative rating in the site database |
Chemical composition (wt %)
| Element | Range | Role |
|---|---|---|
| Ni nickel | about 25.5 | austenitic structure |
| Cr chromium | about 15 | oxidation resistance |
| Ti titanium | about 2.1 | strengthening precipitates |
| Mo molybdenum | about 1.2 | hot strength |
| V vanadium | about 0.30 | |
| B boron | about 0.006 | grain boundary strength |
| Fe iron | balance |
Nominal composition per the AMS specification title for A286. Table properties are minimums per ASTM A453 Grade 660.
Conditions and heat treatment
A286 is supplied solution treated, and gains strength by aging.
| Condition | Properties | When to choose it |
|---|---|---|
| Solution treated | soft, easy to machine and form | machining and forming |
| Solution treated and aged | full strength | bolts and parts |
Applications
- Aerospace bolts and fasteners
- Jet engine parts
- Gas turbine parts
- Hot structures
- High-strength non-magnetic parts
Fabrication
Machining
Difficult: work hardens like nickel alloys (database: 35%). Sharp tools and continuous feed.
Welding
Fair: crack sensitive. Plan welding carefully.
Magnetism
Non-magnetic even after aging.
Compared with similar materials
| Material | Rm / Rp0.2 | Welding | When it is the better choice |
|---|---|---|---|
| Inconel 718 | 1240–1380 / 1035–1170 MPa | Good — ERNiCrMo-6 | Inconel 718: stronger, for higher heat, expensive · material page |
| 17-4 PH (630) | 930–1310 / 725–1170 MPa | Excellent | 17-4 PH: a magnetic PH stainless, for lower heat · material page |
| 304 / 304L | 515–620 / 205–310 MPa | Good — ER308L | 304: an austenitic stainless, weak · material page |
Common mistakes
Using it above about 700 °C
Strength drops. For higher heat, a nickel alloy.
Machining with ordinary steel parameters
It work hardens and wears tools.
Expecting strength without aging
Solution treated, strength is low.
Equivalents, standards and supply
| UNS | S66286 |
|---|---|
| ASTM | A453 Gr. 660 |
| Standards | ASTM A453 Gr. 660 |
| Forms | bar · wire · sheet · forging |
| Producers | Carpenter · ATI · VDM |
Learn more
Values are typical and for comparison only. For design, rely on the standard and on the mill certificate. Sources: ASTM A240, ASTM A276 and EN 10088 (composition), producer data sheets, and the METAL HUB materials database.
Updated: October 31, 2026