Incoloy 660 Plates | UNS S66286 High-Temperature Plates for Steam Turbines, Petrochemical Reactors & Critical Bolting
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During a hot season peak‑load run, a thermal power station in India finally pushed its steam turbine to design temperature only to be pulled back by something as small as bolts and hangers: standard stainless and Cr‑Mo components on the superheater outlet, blade root covers and critical flanges began creeping and relaxing within a few thousand hours, forcing derating, vibration alarms and an unplanned outage to re‑torque and replace overstressed hardware. When the engineering team redesigned these high‑temperature systems around Incoloy 660 Plates (Alloy 660 / A286, UNS S66286, AMS 5525 Grade 660), they leveraged a precipitation‑hardening austenitic alloy whose data sheets show minimum tensile strengths around 895–965 MPa, yield strengths up to roughly 655–725 MPa after solution treatment and ageing, and verified creep‑rupture performance at 650°C with a minimum 385 MPa stress for 100 hours and at least 5% elongation, enabling higher metal temperatures and longer inspection intervals without sacrificing safety or availability.
Incoloy 660 (frequently marketed as Alloy 660, A286 or NAS 660) is an iron‑based, precipitation‑hardened austenitic stainless alloy containing approximately 24–27% nickel, 13.5–16% chromium, around 1–1.5% molybdenum and titanium, vanadium and boron additions, which generate a γ′‑strengthened microstructure for high strength at elevated temperature. Producer and specification literature state that it is designed for high‑temperature use up to about 700–704°C with excellent oxidation resistance, high tensile strength and good creep and stress‑rupture properties, making it suitable for gas‑turbine, steam‑turbine, petrochemical, aerospace and high‑temperature fastening applications.
For procurement heads, design engineers, fabricators, OEMs and hardware or industrial supply stores serving chemical, oil & gas, marine, pharma and power‑generation industries, the central buying decision is whether a more expensive high‑temperature alloy will genuinely deliver lifecycle savings versus borderline stainless or Cr‑Mo steels. Data for Alloy 660 and AMS 5525 Grade 660 show minimum tensile strengths of 895 MPa (130 ksi), 0.2% yield strengths of 585 MPa (85 ksi) for Classes A–C and 725 MPa (105 ksi) for Class D with minimum elongation 15%, plus stress‑rupture performance at 650°C of 385 MPa for 100 h with at least 5% elongation, while Alloy 660 sheet and plate are reported to maintain impressive strength and oxidation resistance up to 700°C, significantly outperforming common stainless grades in creep‑controlled service.
Aurico Alloys LLP can support these requirements as an affordable, authentic Incoloy 660 Plates supplier, manufacturer and stockist in Mumbai, supplying UNS S66286 plate and cut parts in accordance with AMS 5525 / ASME SA453 Grade 660 and associated A286 plate standards, together with NABL‑approved EN 10204 3.1 Mill Test Certificates for steam‑turbine blades and covers, superheater hangers, high‑temperature bolting, petrochemical reactor hardware, offshore components and pharma and chemical‑process equipment. This positioning directly matches searches such as “Incoloy 660 plate suppliers in Mumbai for high-temperature steam turbine blades”, “AMS 5525 Grade 660 plates for power plant fasteners and flange bolting in India”, “High creep-rupture strength Incoloy 660 plates for thermal power generation”, “Incoloy 660 plate price in Mumbai for superheater hangers and support systems”, “UNS S66286 Inconel plates for petrochemical reactors and high-pressure gaskets in India”, “Incoloy 660 plate exporters in Mumbai serving global oilfield service companies” and “Verified Incoloy 660 plate exporters in India with NABL approved Mill Test Certificates (MTC)”.
High-quality Incoloy 660 Plates ready for industrial use.
Specification Overview
| Supplier & Role | Aurico Alloys LLP – Incoloy 660 plate suppliers in Mumbai for high-temperature steam turbine blades, casings, superheater hangers, power‑plant fasteners, petrochemical reactors, refinery valve and pump components and specialised process hardware, with NABL‑approved EN 10204 3.1 Mill Test Certificates. |
|---|---|
| Alloy Description | Precipitation‑hardening austenitic stainless alloy (Alloy 660 / A286) designed for high strength, creep‑rupture resistance and oxidation resistance in service up to approximately 704°C (1300°F). |
| UNS / Werkstoff | UNS S66286; associated with AISI A286, Alloy 660, NAS 660 and 1.4980 in European numbering. |
| Key Standards | AMS 5525 / A453M Grade 660 (ASME SA453 Grade 660) for high‑temperature bolting; A286/Alloy 660 plate and sheet covered by ASTM and AMS specifications for stainless high‑temperature alloys; used in ASME Section I and VIII applications. |
| Design Focus | High tensile and yield strength, good creep‑rupture behaviour at 600–700°C, oxidation resistance in air and combustion atmospheres and stainless‑like weldability for complex shapes and heavy fabrication. |
| Target Users | Power producers, oil & gas and petrochemical operators, marine and naval yards, pharma and chemical processors, aerospace OEMs and hardware and industrial supply stores serving high‑temperature projects. |
UNS & Equivalent Grades
| Property | Value |
|---|---|
| UNS number | S66286 |
| Density | 7.94 g/cm3 |
| Melting range | 1371-1427 °C |
| Plate, sheet and strip specification | AMS 5525 / 5858 |
Identifiers and physical constants for Incoloy 660 (A286). A dash means no such designation is published for this grade.
Stock & Product Availability
As an Incoloy 660 plate stockist in Mumbai, Aurico Alloys LLP can supply solution‑annealed and age‑hardened plates for machining or profiling into steam‑turbine blades and covers, superheater hanger plates, valve and pump components, petrochemical reactor internals, gaskets back‑up rings and heavy bolting, with thickness ranges suitable for both plate fabrication and flange‑bolting applications. Industry descriptions emphasise that Alloy 660 / A286 is malleable and non‑magnetic in many forms, with good corrosion resistance and higher resistance to creep stress and rupture than many standard stainless steels, supporting its use in demanding power and process duty.
This supports high‑intent queries such as “AMS 5525 Grade 660 plates for power plant fasteners and flange bolting in India”, “High creep-rupture strength Incoloy 660 plates for thermal power generation”, “Incoloy 660 plate price in Mumbai for superheater hangers and support systems”, “Incoloy 660 plate stockist in Mumbai for oil refinery valve and pump components”, “Incoloy 660 plate exporters in Mumbai serving global oilfield service companies”, “Aerospace grade Incoloy 660 plates for jet engine exhaust and afterburner parts”, “Marine grade Incoloy 660 plates for specialized high-strength naval hardware”, “ASME SA453 Grade 660 plate stockist for pharmaceutical sterilization equipment”, “Custom cut Incoloy 660 plate sizes for chemical processing and centrifuge components”, “Incoloy 660 age-hardened plates in Mumbai for heavy industrial fabrication” and “Leading Incoloy 660 alloy plate dealers in Mumbai for cryogenic and high-heat applications”.
Chemical Composition
| Element | Min (%) | Max (%) |
|---|---|---|
| Carbon (C) | — | 0.08 |
| Manganese (Mn) | 1.0 | 2.0 |
| Silicon (Si) | — | 1.0 |
| Sulfur (S) | — | 0.015 |
| Phosphorus (P) | — | 0.025 |
| Chromium (Cr) | 13.5 | 16.0 |
| Nickel (Ni) | 24.0 | 27.0 |
| Iron (Fe) | — | Balance |
| Molybdenum (Mo) | 1.0 | 1.5 |
| Titanium (Ti) | 1.90 | 2.35 |
| Aluminium (Al) | — | 0.35 |
| Boron (B) | 0.003 | 0.010 |
| Vanadium (V) | 0.10 | 0.50 |
Composition limits for Incoloy 660 (A286). These are specification limits for the grade, not measured values for a lot; the mill test certificate supplied with your order states the actual analysis.
Mechanical & Physical Properties
| Property | Typical Value – Alloy 660 / A286 / AMS 5525 Grade 660 |
|---|---|
| Tensile Strength (room temperature) | Alloy A286 plate data show typical minimum tensile ≈965–1035 MPa, while AMS 5525 Grade 660 Classes A–D specify ≥895 MPa (130 ksi) minimum. |
| 0.2% Yield Strength (room temperature) | Solution‑treated and aged A286 shows ≈655 MPa yield, with AMS 5525 Grade 660 requiring ≥585 MPa (85 ksi) for Classes A–C and ≥725 MPa (105 ksi) for Class D. |
| Elongation | Typical A286 plate elongation ≈12–25% depending on product; AMS 5525 Grade 660 mandates ≥15% in 4D. |
| Hardness | AMS 5525 Grade 660 Brinell hardness 248–341 HB for Classes A–C and 248–321 HB for Class D, corresponding to Rockwell C roughly 24–35 depending on class. |
| Service Temperature | Alloy 660 / A286 described as suitable for applications up to about 700–704°C (1300°F) with high strength and oxidation resistance. |
| Creep‑Rupture Behaviour | AMS 5525 Grade 660 stress‑rupture requirements specify, for Classes A–C, a minimum stress of 56 ksi (≈385 MPa) at 650°C for 100 h with ≥5% elongation, confirming suitability for long‑term high‑temperature bolting and supports. |
Applications & Benefits
- Power Generation & Steam Turbines: Incoloy 660 plates and AMS 5525 Grade 660 bolting are used for high‑temperature steam turbine blades, discs and casings, superheater hangers and support systems where high creep‑rupture strength, oxidation resistance and stable preload are essential for thermal power generation.
- Oil, Gas & Petrochemical: UNS S66286 plates serve as high‑strength materials for oil refinery valve and pump components, high‑pressure petrochemical reactors, gasket back‑up rings and offshore exploration and subsea equipment where both strength and moderate corrosion resistance are needed under elevated temperatures.
- Aerospace, Marine & Pharma: Aerospace‑grade Alloy 660 plate is used in jet engine exhaust and afterburner parts, while marine‑grade plates are applied in specialised high‑strength naval hardware and shaft supports; ASME SA453 Grade 660 is also used for high‑temperature bolting in pharmaceutical sterilisation equipment and high‑speed chemical centrifuges.
- Sourcing & Compliance: Verified Incoloy 660 plate exporters in India provide solution‑treated and age‑hardened plates with NABL‑approved MTCs, supporting heavy industrial fabrication, cryogenic and high‑heat applications and integration into ASME‑coded systems for turbines, reactors and high‑temperature pipelines.
FAQ & Search Trends
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Domestic Supply Network
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Conclusion
Incoloy 660 Plates from Aurico Alloys LLP, supplied as UNS S66286 Alloy 660 / A286 in line with AMS 5525 / ASME SA453 Grade 660 and associated high‑temperature plate standards and supported by NABL‑approved Mill Test Certificates, give chemical, oil & gas, marine, pharma and power‑generation users a precipitation‑hardened austenitic alloy that combines stainless‑like fabrication with high tensile and creep‑rupture strength up to about 704°C for turbine blades, superheater hangers, petrochemical reactors, offshore and naval hardware and high‑temperature process equipment are your most temperature‑critical and load‑bearing assets still relying on borderline stainless and Cr‑Mo steels instead of purpose‑engineered Incoloy 660 plates?