Incoloy A-286/UNS S66286/W-Nr. 1.4980/Alloy A-286 bar

Incoloy A-286 bar, designated as UNS S66286, material number W.Nr. 1.4980, and commonly known as Alloy A-286, is a precipitation-hardenable iron-nickel-chromium superalloy known for its high strength and excellent corrosion resistance at temperatures up to about 700°C (1300°F). This bar stock form is a vital material for machining high-stress components such as fasteners, turbine blades, and engine parts in aerospace, automotive, and industrial applications where a combination of strength, toughness, and oxidation resistance is required.

Introduction to Incoloy A-286 (Alloy A-286)

Incoloy A-286 is an age-hardenable austenitic superalloy that achieves its high strength through precipitation of gamma prime (γ’) phase during heat treatment. While classified as an iron-based alloy, its high nickel and chromium content gives it corrosion resistance superior to many stainless steels and allows it to retain strength at elevated temperatures. The bar stock is particularly valued for its good fabricability in the solution-annealed condition, which can then be aged to achieve high strength, making it ideal for complex machined or forged parts.

Chemical Composition of Incoloy A-286 Bar

The balance of elements in Incoloy A-286 bar is carefully controlled to enable both precipitation hardening and good environmental resistance. Supplied by Shanghai NC Metal Materials Co., Ltd., the bar stock meets aerospace and industrial specifications ensuring consistent performance.

Mechanical Properties of Incoloy A-286 Bar (Heat Treated)

The mechanical properties of Incoloy A-286 bar are developed through a specific solution treatment and aging process. Bar is typically supplied in the solution-annealed condition (Condition A) for fabrication, then aged to achieve high strength.

Typical Value (Aged Condition – Grade 660)

Physical Properties of Incoloy A-286 Bar

The physical properties of Alloy A-286 are important for applications involving thermal cycling and weight considerations.

Notes / Condition

Standard Specifications, Bar Forms, and Available Sizes

Shanghai NC Metal Materials Co., Ltd. supplies Incoloy A-286 bar in various forms and tempers, primarily to aerospace and high-temperature bolting specifications.

Primary Applications of Incoloy A-286 Bar Stock

Machined or forged components from Incoloy A-286 bar are essential in high-stress, elevated-temperature applications: Aerospace: Turbine engine components (blades, disks, casings), afterburner parts, and high-strength fasteners (bolts, nuts, studs). Automotive: Turbocharger components and high-performance engine valves. Industrial Gas Turbines: Bolting, blades, and discs. Power Generation: High-temperature bolts and studs for steam turbines and piping. High-Temperature Fasteners: The premier material for ASTM A453 Grade 660 bolts used in refinery, chemical, and power plant applications.

Heat Treatment of Incoloy A-286 Bar

The properties of A-286 are developed through a standard heat treatment sequence: Solution Treatment: Heat to 980°C (1800°F), hold, then cool rapidly (water quench or oil quench). This dissolves the alloying elements into the austenitic matrix. Aging Treatment: Reheat to 720°C (1325°F) for 16 hours, then air cool. This step precipitates the fine gamma prime (γ’) phase throughout the matrix, providing the high strength. Variations in time and temperature can adjust strength and ductility balance.

Machining and Fabrication of Incoloy A-286 Bar

Machining A-286 bar is best performed in the softer, solution-annealed condition before final aging. In this state, it machines similarly to other austenitic stainless steels but is tougher. Recommendations include: using rigid setups and sharp carbide tools; moderate speeds and feeds; and ample coolant. Machining in the fully aged condition is difficult due to high strength and hardness, requiring slower speeds, positive rake tools, and careful technique. The alloy is readily forgeable in the temperature range of 925-1200°C (1700-2200°F).

Welding of Incoloy A-286 Bar

Incoloy A-286 is weldable, but the process requires care to avoid cracking and to preserve properties. Welding should be performed in the solution-annealed condition. Post-weld heat treatment (full solution treat and age) is essential to restore mechanical properties and corrosion resistance in the weld zone. Matching filler metals (e.g., ERNiFeCr-1) or nickel-based fillers like 625 are often used. Resistance welding processes are commonly and successfully used for this alloy.

Reference Pricing and Key Purchasing Factors

The price of Incoloy A-286 bar from Shanghai NC Metal Materials Co., Ltd. is influenced by its nickel content, specialized heat treatment requirements, and stringent quality controls for aerospace applications.