321 Stainless Steel Plate: Properties, Price & Supplier Guide

Looking to buy 321 stainless steel plate? This guide covers what makes 321 different from 304, the sizes and surfaces we stock, the price drivers, and how to choose a reliable supplier — with a fast quote path at the end.

Why Choose 321 Stainless Steel Plate

321 is a titanium-stabilized austenitic grade (ASTM A240). The added titanium (about 5x carbon) ties up carbon and prevents chromium-carbide precipitation in the 425-815°C range, so 321 resists intergranular corrosion after welding and in continuous high-temperature service where 304 would sensitize. If your part sees heat, 321 plate is the safer choice.

Specifications, Sizes & Surfaces

We stock 321 plate from 0.5 mm to 80 mm thick, in widths of 1000/1219/1500/2000 mm and lengths up to 6000 mm. Common surfaces: No.1 (hot-rolled, annealed), 2B, BA, No.4 brushed and 8K mirror. Chemistry: 17-19% Cr, 9-12% Ni, Ti 5xC min. Dual-certified to ASTM A240 and EN 1.4541 on request.

321 Plate Price Factors

Price per kg tracks nickel and chromium surcharge plus the titanium addition. Thickness and surface finish add cost — mirror-polished 8K costs more than No.1. Volume and repeat orders earn deeper discounts. Send your spec for a current USD/kg quote; we hold 100,000 tons so even thick plates ship fast.

Typical Applications

321 plate is used in exhaust manifolds and headers, heat-exchanger shells, aircraft exhaust systems, welded tanks and ducts in the 400-800°C band, and refinery and furnace components. Its weldability without post-weld sensitization makes it a fabrication favorite.

How to Choose a Supplier

Ask for MTC (EN 10204 3.1), confirm the mill certificate shows titanium, and verify stock depth and lead time. A supplier with 100,000 tons on hand and ISO/TS16949 certification can cover trial lots and full containers alike, with cut-to-size and third-party inspection.

Frequently Asked Questions About stainless steel plate