Inconel 625 Sheet (UNS N06625, ASTM B443)

What Inconel 625 Sheet Is

Inconel 625 is a nickel-base alloy from the nickel-chromium-molybdenum family. Its high nickel and chromium content gives oxidation resistance at elevated temperature, while molybdenum and niobium add strength and resistance to pitting, crevice attack, and chloride stress-corrosion cracking. In thin gauge, that same chemistry lets fabricators form, roll, and weld parts that must survive hot, chloride-bearing, or acidic service where austenitic stainless runs out of margin.

Sheet is the form of choice where the section is light but the duty is severe: liners and linings, bellows and expansion joints, heat shields, exhaust and flare components, formed covers, and chemical-process internals. Our 625 sheet is supplied solution-annealed and ready for shearing, forming, and welding, with full traceability back to the heat.

For the wider alloy context, see our overview of nickel alloys and where each family fits.

Grade, Standard, and Designation

Inconel 625 sheet conforms to ASTM B443, the plate, sheet, and strip specification for the grade. The UNS number is N06625. Read the full scope of the standard on our ASTM B443 reference page, and cross-check international equivalents on the UNS, Werkstoff, and JIS cross-reference.

Why Specifiers Choose Inconel 625 Sheet

Buyers reach for 625 sheet when a light-gauge part has to survive more than one attack mode at once. The alloy resists pitting and crevice corrosion in chlorides, resists the chloride stress-corrosion cracking that limits austenitic stainless, and holds strength and oxidation resistance at high temperature. For an explanation of how pitting resistance is ranked, see our guide to PREN and pitting-resistance equivalent.

Where the duty is sour, acidic, or hot and chloride-laden, 625 often sits one step beyond 904L or Incoloy 825 on the selection ladder. If your service leans toward combined reducing and oxidizing acids or sour gas, compare the two directly in our Incoloy 825 vs Inconel 625 comparison, and review the Incoloy 825 grade page before you finalize the purchase order.

Typical Applications

Inconel 625 sheet is specified across industries where temperature, pressure, and corrosion overlap:

• Oil and gas, including sour and high-chloride service
• Petrochemical process equipment and linings
• Chemical and acid processing vessel internals and liners
• Pollution control and FGD scrubber and ductwork components
• Marine and seawater-exposed structures

Corrosion and Service Behavior

The value of 625 is the breadth of its resistance. Molybdenum and niobium raise resistance to localized pitting corrosion, while the nickel-rich matrix is largely immune to the chloride stress-corrosion cracking that affects austenitic stainless. For sour duty, specify the acceptance criteria clearly and reference NACE MR0175 / ISO 15156 on the order so the heat is supplied in the qualified condition.

Thin-gauge welded fabrications heat up and cool fast, so keep heat input controlled to protect the heat-affected zone. Background on filler choice and procedure is in our note on welding stainless and nickel alloys, and the general risk of intergranular corrosion is worth reviewing before you set the weld procedure.

Sizes, Thickness, and Cutting

We stock 625 sheet across a range of thin gauges and can shear or cut to your plan. To estimate shipping or fabrication weight, use the weight calculator or follow the method in how to calculate steel plate weight. If you are still choosing between forms, the explainer on sheet vs plate vs coil will help you land the right one, and heavier sections are covered on the Inconel 625 plate page.

Matching Forms and Fittings

For a complete 625 system, we also supply matching product forms:

Quality, Traceability, and Certification

Nandini Steel has supplied corrosion-resistant and high-temperature steel since 2003 and is ISO 9001:2015 certified. Every order ships with an EN 10204 3.1 or 3.2 mill test certificate, so the chemistry and mechanical properties are traceable to the heat. Learn how to read one in our guide to the mill test certificate and the EN 10204 standard reference, and see our quality assurance and certifications pages for the full picture.

Frequently Asked Questions

Request a Quote

Tell us your gauge, dimensions, and quantity and we will confirm stock and live pricing. Reach the Nandini Steel team on +91 99202 09184 (WhatsApp), email reachus@nandinisteel.com, or use our contact page to send an RFQ.

Part of our steel sheet range.