Name: Incoloy 20
Brand: Incoloy

Material Overview

Incoloy 20 material profile

A concise grade introduction for buyers who need to confirm composition, properties, standards, available forms and suitable applications before sending an inquiry.

Engineering profile

Incoloy 20, also known as Alloy 20, 20Cb-3 and UNS N08020, is a niobium-stabilized nickel-iron-chromium alloy developed for corrosion resistance in sulfuric acid service. Its combination of nickel, chromium, molybdenum and copper provides useful resistance to general corrosion, pitting and crevice corrosion in selected chemical environments, while niobium stabilization helps reduce sensitization and intergranular corrosion around welded areas. The alloy is commonly supplied for chemical process piping, heat exchangers, mixing tanks, pickling equipment, pumps, valves, fasteners and fabricated process equipment.

Technical data on this page is for material selection reference. Final acceptance values should be confirmed by the purchase standard, heat treatment condition, product form, size and material test certificate.

Chemical Composition

Incoloy 20 composition range

The following table shows common limiting composition values for Alloy 625 / UNS N06625. Actual product chemistry is reported by heat on the material test certificate.

Element	Symbol	Composition, wt.%	Role in Incoloy 20
Nickel	Ni	32.0-38.0	Supports corrosion resistance and a stable austenitic structure.
Chromium	Cr	19.0-21.0	Improves resistance to oxidizing media and general corrosion.
Copper	Cu	3.0-4.0	Provides important resistance in sulfuric acid environments.
Molybdenum	Mo	2.0-3.0	Improves resistance to localized corrosion and reducing media.
Niobium + Tantalum	Nb + Ta	8 x C min, 1.0 max	Stabilizes carbon and helps reduce sensitization around welds.
Iron	Fe	Balance	Forms the balance of the austenitic alloy matrix.
Manganese	Mn	2.0 max	Controlled as a minor alloying and deoxidizing element.
Silicon	Si	1.0 max	Controlled to support processing and weldability.
Carbon	C	0.07 max	Limited to help control carbide formation and sensitization.
Phosphorus	P	0.045 max	Controlled residual element.
Sulfur	S	0.035 max	Controlled residual element for processing and weld quality.

Physical Properties

Key physical and thermal data

These values help customers compare density, thermal behavior, magnetic response and conductivity during early material selection.

Property	Metric Value	Imperial Value	Condition / Notes
Density	8.08 g/cm3	0.292 lb/in3	Room temperature
Modulus of Elasticity	193 GPa	28 x 10³ ksi	Room temperature
Shear Modulus	76 GPa	11 x 10³ ksi	Room temperature
Specific Heat	500 J/kg·°C	0.12 Btu/lb·°F	Room-temperature typical value
Thermal Conductivity	12.3 W/m·°C	85 Btu·in/ft²·h·°F	Room-temperature typical value
Electrical Resistivity	1.08 µΩ·m	651 ohm-cmil/ft	Room-temperature typical value
Mean Coefficient of Thermal Expansion	14.7 µm/m·°C	8.2 x 10^-6 in/in·°F	Mean value from 25 to 100 °C

Mechanical Properties

Room-temperature mechanical properties

Mechanical properties vary with product form, size, processing route and heat treatment. The table below summarizes commonly referenced nominal values for material selection.

Product Form / Condition	Tensile Strength	Yield Strength, 0.2%	Elongation	Technical Note
Annealed wrought material	Approx. 620 MPa (90 ksi)	Approx. 300 MPa (45 ksi)	Approx. 40%	Representative room-temperature properties, not guaranteed specification minima.
Plate, sheet and strip	Specification dependent	Specification dependent	Specification dependent	Acceptance values depend on thickness, heat treatment and the applicable purchase specification.
Rod, bar and wire	Specification dependent	Specification dependent	Specification dependent	Cold work can increase strength while reducing ductility.
Pipe and tube	Specification dependent	Specification dependent	Specification dependent	Confirm construction method, dimensions, delivery condition and testing requirements.
Forgings, flanges and fittings	Specification dependent	Specification dependent	Specification dependent	Properties depend on section size, solution treatment and governing product standard.

Values shown are representative rather than guaranteed acceptance criteria. Final mechanical requirements must be confirmed against the applicable product specification, dimensions, delivery condition and material test certificate.

For pressure equipment, aerospace parts or project-specific acceptance, use the minimum requirements in the specified ASTM, ASME, AMS, EN or customer drawing rather than nominal values.

Standards & Specifications

Common Incoloy 20 standards by product form

YSN128 can quote Alloy 625 products according to ASTM, ASME, AMS, EN, DIN, ISO or customer drawing requirements. Certificate scope can be matched to the purchase order.

Product Form	Common Standard	Current Status / Use	Certificate / Inspection
Plate, Sheet, Strip	ASTM B463	Withdrawn in April 2026 without replacement; use only when required by an existing contract or project specification and verify current purchaser requirements.	EN 10204 3.1 MTC, chemistry, mechanical testing, PMI and dimensional inspection as specified
Rod and Bar	ASTM B473	Active standard covering nickel alloy bar and wire including UNS N08020; confirm the required edition.	MTC, PMI, mechanical testing and dimensional inspection
Weaving Wire	ASTM B475	Active standard for nickel alloy weaving wire including UNS N08020; confirm the required edition.	MTC, diameter inspection and surface examination
Seamless Pipe & Tube	ASTM B729	Withdrawn in March 2026 without replacement; treat as a historical or project-specified requirement.	Hydrostatic or nondestructive testing, MTC and dimensional inspection as specified
Welded Pipe	ASTM B464 / B464M	Withdrawn in December 2025 without replacement; use only when contractually specified.	Weld examination, pressure or nondestructive testing and MTC
Welded Heat Exchanger Tube	ASTM B468	Withdrawn in December 2025 without replacement; verify the project specification before ordering.	Eddy-current or other specified NDT, dimensional inspection and MTC
Electric-Fusion-Welded Large Pipe	ASTM B474 / B474M	Commonly referenced for large welded pipe; verify the current edition and purchaser requirements.	Weld inspection, radiography or other specified NDT, pressure test and MTC
Forgings, Flanges, Fittings and Valve Parts	ASTM B462	Active standard covering forged products including UNS N08020; confirm the required edition.	Heat-treatment record, mechanical testing, PMI, UT when specified and MTC
Welding Electrodes and Wire	AWS A5.4 E320LR / AWS A5.9 ER320LR	Common low-residual welding consumable classifications for Alloy 20 fabrication.	Consumable certificate, chemistry and lot identification

Available Product Forms

Incoloy 20 supply range

Review available product forms, size ranges, standards and delivery options for this alloy.

Form	Common Size Range	Delivery Condition	Typical Applications	Page Link
Pipe & Tube	OD 6-610 mm, wall thickness or schedule to specification	Seamless or welded, solution annealed, pickled	Sulfuric acid piping, heat exchangers and chemical transfer systems	View Pipe & Tube
Round Bar	Diameter 3-300 mm, larger forged sizes and cut lengths available	Hot rolled, forged, solution annealed, peeled or polished	Pump shafts, valve stems, fasteners and machined process components	View Round Bar
Sheet & Plate	Thickness 0.5-100 mm, custom widths, lengths and cut parts	Solution annealed, pickled, cold rolled or polished	Mixing tanks, pickling equipment, vessels and heat exchanger parts	View Sheet & Plate
Strip & Foil	Thickness 0.02-3 mm, slit widths and coil weights to specification	Cold rolled, solution annealed, bright or pickled	Gaskets, seals, diaphragms and formed corrosion-resistant components	View Strip & Foil
Wire	Diameter 0.1-12 mm, coil, spool or straight-length supply	Cold drawn, annealed, bright or pickled	Mesh, screens, springs, tie wire and fastener manufacturing	View Wire
Fasteners	Standard and custom bolts, nuts, screws, studs and washers	Solution annealed, machined, rolled thread or custom finished	Chemical plants, acid-processing equipment, pumps and valves	View Fasteners
Fittings	ASME, EN and drawing-based elbows, tees, reducers and caps	Seamless or welded, solution annealed and machined	Acid process lines, chemical piping and heat exchanger connections	View Fittings
Flanges	ASME B16.5, ASME B16.47, EN or custom dimensions	Forged, solution annealed, machined and inspected	Process piping, pressure equipment, valves and pump connections	View Flanges
Forgings	Rings, discs, blocks, shafts and drawing-based components	Forged, solution heat treated, rough or finish machined	Pump bodies, valve parts, pressure components and custom equipment	View Forgings
Welding Wire	Diameter 0.8-4.0 mm, spool, coil or straight-length supply	Clean bright finish, precision drawn and controlled chemistry	Joining Alloy 20, repair welding and corrosion-resistant overlay	View Welding Wire

Material Selection Guide

When to consider Incoloy 20

This guide helps buyers connect service conditions with the typical advantage of Alloy 625. Final selection should consider medium concentration, temperature, pressure, fabrication, availability and budget.

Service Requirement	Why Incoloy 20 Helps	Common Product Form	Buyer Note
Sulfuric acid process equipment	Copper, nickel, chromium and molybdenum provide useful corrosion resistance across selected sulfuric acid conditions.	Plate, sheet, pipe, tube, fittings and forgings	Provide acid concentration, temperature, impurities, aeration and flow conditions for material review.
Resistance to localized corrosion	Molybdenum and chromium improve resistance to pitting and crevice corrosion in selected process media.	Pipe, tube, plate, fasteners and fittings	Confirm chloride concentration, temperature, deposits and crevice conditions.
Welded chemical equipment	Niobium stabilization helps reduce sensitization and intergranular corrosion around welded areas.	Plate, sheet, pipe, tube and fabricated assemblies	Use a qualified welding procedure and compatible low-residual filler metal.
Pickling and acid-cleaning systems	The alloy provides useful resistance in selected mixed-acid and contaminated acid solutions.	Tanks, coils, pipe, fittings, pumps and valves	Review every acid component, contaminant, concentration and operating temperature.
Pharmaceutical, food and synthetic-material processing	Provides corrosion resistance and fabricability for selected chemical process streams.	Vessels, piping, heat exchanger parts and fittings	Confirm cleaning chemicals, sanitary finish and contamination-control requirements.
Pumps, valves and fasteners	Combines corrosion resistance with useful room-temperature strength and machinability.	Bar, forgings, fasteners, flanges and fittings	Specify dimensions, pressure class, machining allowance and inspection requirements.

Why Choose Us

Supply and quality support for Incoloy 20

For ranking traffic, buyers need more than a data sheet. This section gives clear trust signals for procurement, engineering and quality teams.

STASTM / ASME / AMS / EN

Quotation can be matched to project standards and product form specifications.

MTEN10204 3.1 MTC

Heat number, chemistry, mechanical properties and inspection records can be supplied.

QCPMI & Inspection

PMI, UT, dimensional inspection, visual inspection and packing check are available.

CSCustom Size

Cutting, machining allowance, rough machining and drawing-based supply can be arranged.

EPExport Packing

Wooden case, bundle, waterproof protection and international shipping documents.

RFFast Technical Reply

Send grade, size, standard, quantity and destination for a practical quotation route.

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FAQ

Incoloy 20 questions from buyers

Find practical answers about procurement, standards, fabrication and industrial applications.

Incoloy 20 is mainly used for sulfuric acid equipment and other chemical process systems. Typical products include mixing tanks, heat exchangers, process piping, pickling equipment, pumps, valves, fasteners, fittings and fabricated vessels.

Yes. UNS N08020 is the standardized UNS designation for Incoloy 20. The material is also commonly called Alloy 20, 20Cb-3, INCOLOY alloy 020 or Werkstoff 2.4660.

Alloy 20 contains substantially more nickel as well as copper and molybdenum, giving it better performance than 316L in many sulfuric acid and selected aggressive chemical environments. The correct choice still depends on acid concentration, temperature, contaminants and flow conditions.

We can quote plate, sheet, strip, foil, round bar, rod, wire, seamless or welded pipe and tube, fasteners, fittings, flanges, forgings and welding wire. Custom dimensions, cut pieces and drawing-based components can also be discussed.

ASTM B473 is commonly used for bar and wire, while ASTM B462 covers forgings, flanges, fittings and valve parts. ASTM B463, B729, B464 and B468 were traditionally used for other wrought and tubular products but were withdrawn in 2025 or 2026, so current project and purchaser requirements must be verified before ordering.

Yes. Shielded fusion and resistance welding processes can be used with a qualified procedure. AWS E320LR or ER320LR consumables are commonly selected. Clean joint surfaces, low restraint, controlled heat input, stringer beads and an interpass temperature of approximately 150 °C maximum are generally recommended. Oxyacetylene welding should be avoided because of possible carbon pickup.

Incoloy 20 was developed specifically for useful resistance in sulfuric acid service, but it is not suitable for every concentration and temperature. Material selection should consider acid concentration, operating temperature, impurities, aeration, velocity, deposits and expected shutdown conditions.

Please provide the grade or UNS number, product form, dimensions, quantity, applicable standard, delivery condition, certificate requirements and destination. For corrosion review, also provide the complete process chemistry, concentration, temperature, pressure, flow conditions and any inspection or drawing requirements.

Incoloy 20