inconel 600 vs inconel 625

Inconel 600 is a nickel-chromium alloy with good oxidation resistance and strength at high temperatures. It is widely used in heat-treatment equipment, chemical processing, and nuclear applications.
Inconel 625 contains molybdenum and niobium, giving it higher strength and better resistance to pitting, crevice corrosion, and seawater corrosion. It is commonly used in marine, offshore, aerospace, and chemical equipment.

Grade A

inconel 600

UNS: N06600
Family: Inconel / Nickel-Chromium Alloy
Common Forms: Plate, sheet, pipe, tube, bar, flange

A nickel-chromium alloy known for high-temperature oxidation resistance and good mechanical strength, widely used in heat treatment, chemical processing, furnace components and nuclear equipment.

View inconel 600

Grade B

inconel 625

UNS: N06625
Family: Inconel / Nickel-Chromium-Molybdenum Alloy
Common Forms: Plate, sheet, pipe, tube, bar, flange

A high-strength nickel-chromium-molybdenum alloy with excellent corrosion and fatigue resistance, widely used in marine systems, chemical processing, aerospace equipment and offshore applications.

View inconel 625

Main Comparison

inconel 600 and inconel 625 comparison by engineering and purchasing factors

Review the key differences before confirming chemical media, product form, standard, certificate and delivery schedule.

Comparison Item	Inconel 600	Inconel 625	Selection Note
Basic Information
UNS Number	N06600	N06625	Use the UNS number on drawings, MTCs and purchase specifications.
Alloy Type	Nickel-chromium-iron alloy	Nickel-chromium-molybdenum-niobium alloy	600 emphasizes heat and oxidation resistance; 625 combines high strength with broader corrosion resistance.
Typical Product Forms	Plate, sheet, strip, pipe, tube, bar, wire and fittings	Plate, sheet, pipe, tube, bar, wire, forgings and fittings	Actual availability depends on size, standard, quantity and delivery schedule.
Chemical Composition
Nickel (Ni)	72.0% min	58.0% min	600 contains more nickel, supporting resistance to reducing environments and chloride stress-corrosion cracking.
Chromium (Cr)	14.0–17.0%	20.0–23.0%	The higher chromium content of 625 improves oxidation and general corrosion resistance.
Molybdenum (Mo)	Not intentionally added	8.0–10.0%	Molybdenum gives 625 substantially better pitting and crevice-corrosion resistance.
Niobium + Tantalum (Nb + Ta)	Not intentionally added	3.15–4.15%	Niobium strengthens 625 without requiring precipitation-hardening heat treatment.
Iron (Fe)	6.0–10.0%	5.0% max	600 contains more iron as a principal alloying component.
Carbon (C)	0.15% max	0.10% max	Final composition limits should follow the applicable product specification.
Mechanical Properties
Yield Strength, RT	Approx. 240 MPa	Approx. 414 MPa	Typical annealed values; 625 provides considerably higher room-temperature strength.
Tensile Strength, RT	Approx. 550 MPa	Approx. 827 MPa	625 is preferred when mechanical strength is an important design requirement.
Elongation, RT	Approx. 30%	Approx. 30%	Both alloys retain useful ductility in the annealed condition.
Strengthening Method	Solid-solution strengthened	Solid-solution strengthened by molybdenum and niobium	Neither alloy normally requires age hardening for standard applications.
Weldability	Good with qualified procedures	Excellent with qualified procedures	Confirm filler metal, heat input and inspection requirements for the service environment.
Price Comparison
Relative Material Cost	High	Higher	625 generally costs more because of its molybdenum and niobium content.
Stock Availability	Commonly available in standard sheet, tube, pipe and bar sizes	Widely available in plate, pipe, tube, bar, forgings and fittings	Availability varies by product form, dimension, specification and regional inventory.
Quotation Factors	Form, size, quantity, specification, testing and nickel market price	Form, size, quantity, specification, testing and nickel/molybdenum market prices	Obtain quotations using the actual drawing, tolerances, certification and delivery requirements.
Performance & Application
Corrosion Resistance	Good resistance to oxidation, carburization and many reducing environments	Excellent resistance to pitting, crevice corrosion and chloride-containing media	625 offers broader corrosion resistance, especially in marine and chloride service.
High-Temperature Performance	Excellent oxidation resistance at elevated temperatures	High strength and good oxidation resistance at elevated temperatures	Choose 600 for many furnace environments and 625 when both heat resistance and high strength are required.
Typical Applications	Furnace components, heat-treatment equipment, chemical equipment and nuclear steam-generator tubing	Marine equipment, offshore piping, chemical processing, aerospace exhaust systems and pollution-control equipment	Selection should reflect the actual medium, temperature, pressure and mechanical loading.
Best Use Case	High-temperature oxidation service where moderate strength is sufficient	Severe corrosion service requiring high strength and chloride resistance	Use project specifications and verified corrosion data for final material selection.

Values are typical references for article comparison. Final supply should follow the ordered standard, product form, heat treatment, mill test certificate and project requirements.

Choose Choose inconel 600 when

High-temperature oxidation, carburization or resistance to chloride-ion stress-corrosion cracking is the key issue.
The equipment will operate in furnace, heat-treatment, nuclear or caustic alkali environments.
You need good thermal stability and mechanical performance across a wide temperature range.

Choose inconel 625 when

Seawater, chlorides or severe pitting and crevice corrosion is the key issue.
The equipment may face aggressive offshore, marine, chemical processing or sour gas conditions.
You need high strength, excellent weldability and strong corrosion resistance without post-weld heat treatment.

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