Type A-286 (UNS S66286)


A-286 is a Ni-Cr austenitic precipitation-hardened iron-based steel that is one of the original superalloys. It has been used for applications requiring high strength and corrosion resistance up to 1,300°F (704°C), and for cryogenic applications. Its relatively low alloy content and low-cost formulation make it an excellent choice for many applications. A-286 alloy is typically produced by vacuum induction melting (VIM), followed by vacuum arc (VAR) or electroslag (ESR) remelting. Applications include jet engine, supercharger, and missile components including: wheels and blades, casings, afterburner and sound suppressor parts, fuel nozzles, fasteners, extrusion tooling and miscellaneous hardware. This alloy is designated Grade or Type 660 in several specifications.

Chemical Composition

Chemical Composition (wt%) limits as specified in ASTM A638 and ASME SA638*

Carbon 0.08 Silicon 1.00
Chromium 13.50-16.00 Phosphorus 0.040
Nickel 24.00-27.00 Sulfur 0.030
Molybdenum 1.00-1.50 Aluminum 0.35
Titanium 1.90-2.35 Vanadium 0.10-0.50
Manganese 2.00 Boron 0.0010-0.010

*Maximum, unless range is indicated

Physical Properties

Physical properties for A-286

Density, lb/in3 0.287
Modulus of Elasticity, psi 29.1x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 9.2 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 8.7
Specific Heat, Btu/lb ˚F 0.10
Electrical Resistivity, Microhm-in 35.8

Mechanical Properties

Mechanical property requirements for heat treated product as specified in ASTM A638 and ASME SA638

Yield Strength, min. (ksi) 85
Tensile Strength, min. (ksi) 130
Elongation, min. (%) 40


Typical standards for A-286

AMS 5731
AMS 5732
AMS 5734
AMS 5737