GB/T 4237 06Cr25Ni20 S31008 Stainless Steel Plate Supplier

06Cr25Ni20 is 310S: 24–26% chromium and 19–22% nickel for oxidation resistance to about 1 100 °C in air. Silicon up to 1.50% helps scaling resistance.

How to read the name: under GB/T 20878 the leading ’06’ is the carbon code (here C ≤0.08%), then Cr25 = about 25% chromium; Ni20 = about 20% nickel. S31008 is the unified numeric code (ISC) used in GB/T 4237-2015. Older drawings and Chinese buyers may still write the pre-2007 name 0Cr25Ni20.

SHH STEEL produces and exports austenitic stainless plate from China, works as a sales agent for leading stainless mills, and runs its own processing warehouse for cutting and surface finishing. 06Cr25Ni20 is part of our GB/T 4237 stainless plate range; for comparison, see our ASTM A240 Type 310S page.

For hot service, 06Cr25Ni20 competes with the other heat-resistant austenitics in GB/T 4237. Temperature limits below are typical industry guidance for clean, dry air, not values from the standard; sulfur, vanadium, chlorine and thermal cycling lower them.

Sigma phase forms in all of these grades during long exposure at 650–900 °C. It does not hurt hot strength much, but it makes the plate brittle at room temperature, which matters during shutdowns and maintenance.

Values are maximum unless a range is given. The mill reports the ladle (heat) analysis on the certificate; this is the figure to compare with Table 15.

A check analysis drilled from the finished plate may differ slightly from the heat analysis. GB/T 4237 refers to GB/T 222 for the permitted deviations; the table applies them to the 06Cr25Ni20 limits. Deviations apply to one side of a range only, never to both sides in the same heat.

Where the table says ‘by agreement’, the deviation is not tabulated for that content level and should be agreed in the contract, usually by reference to ASTM A480 Table A1.1.

Values apply to plate in the delivery heat-treated condition, tested transversely per GB/T 228.1. Hardness is checked by one method chosen by the mill.

Recommended heat treatment for 06Cr25Ni20 (GB/T 4237-2015 Annex C): ≥ 1 040 °C, water quench or other rapid cooling.

For hot service the plate is used in the solution-annealed condition; in-service ageing changes properties and is part of the design.

Equivalent grades are close in chemistry and properties but are never identical: limits on carbon, nitrogen and residual elements differ. For dual or multiple certification the heat must meet every standard named on the order, and we confirm that from the heat chemistry before quotation.

Related pages: ASTM A240 Type 310S, ASME SA240 310S, JIS G4305 SUS310S, AISI 310S. See also our ASTM A240/A240M and JIS G4305 plate lists.

Sister grades on the same standard are listed under GB/T 4237; cold-rolled sheet of the same chemistry is ordered to GB/T 3280, and all our plate lines sit in stainless steel sheets and plates.

Weld with matching filler (ER309/309L for 23-13, ER310 for 25-20, Ce-bearing fillers for the rare-earth grades) to keep oxidation resistance across the joint.

Fully austenitic weld metal is prone to hot cracking: keep heat input moderate, use convex beads and clean joints of sulfur, oil and paint. Avoid long holds at 650–900 °C before service where sigma phase can form.

Cutting: we cut 06Cr25Ni20 by plasma (up to about 150 mm), laser (thin plate) or waterjet, and remove the heat-affected edge by machining where the drawing requires it.

The table compares 06Cr25Ni20 with the grades buyers most often weigh it against. Strength values are GB/T 4237-2015 minimums; PREN is calculated from the minimum chemistry.

310S is weak in sulfidizing atmospheres because of its high nickel; choose a high-Cr low-Ni option or aluminized parts there. It also embrittles by sigma phase at 650–900 °C. The ‘S’ grade (C ≤0.08%) is the normal plate choice.

Hot-service applications:

• Furnace muffles, retorts and radiant tubes
• Heat treatment baskets and conveyor parts
• Burners, kilns and incinerator parts
• Cryogenic parts (fully austenitic, non-magnetic)

Buyers specifying 06Cr25Ni20 for these jobs often compare it with GB/T 4237 06Cr23Ni13 S30908 and GB/T 4237 05Cr19Ni10Si2CeN S30450; the comparison table on this page shows the differences.

Our warehouse cuts plate to size (plasma, laser, waterjet, saw), bevels weld edges, polishes and applies PVC protective film. Processed plate ships with the original mill heat number marked. Ask for cut pieces of other stainless steel products at the same time to consolidate freight.

Weight: plate mass in kg/m² = thickness (mm) × density (7.98 g/cm³). A 10 mm 06Cr25Ni20 plate weighs about 79.8 kg/m²; a 1 500 × 6 000 × 10 mm plate about 718 kg.

• Heat chemical analysis on every heat; product analysis by agreement
• Tensile test (Rp0.2, Rm, A) per batch
• Hardness test
• Ultrasonic testing (NB/T 47013.3 or ASTM A578) when specified
• Positive material identification (PMI) on every plate leaving our warehouse
• Visual and dimensional inspection; third-party inspection (SGS, BV, TÜV, Intertek) at the buyer’s request

Certificates follow EN 10204 3.1 as standard. Where plate is also certified to ASME SA240 or ASTM A240, both standards are shown on one certificate.

• Standard and edition: GB/T 4237-2015
• Grade and code: 06Cr25Ni20 (S31008); add the equivalent if dual certification is needed
• Thickness × width × length, quantity in pieces or tonnes
• Thickness tolerance class and flatness if tighter than standard
• Surface finish and protective film
• Tests beyond the standard (IGC, UT, impact, ferrite, PMI, grain size)
• Certificate type (EN 10204 3.1 / 3.2) and inspection body
• Marking, packing (wooden cases, steel pallets) and delivery terms

Send the list to SHH STEEL and we return a quotation with mill, lead time and stock options. Other grades from the same standard can be combined in one shipment; browse GB/T 4237 plate grades.

06Cr25Ni20 is a mainstream grade at Chinese stainless mills. We supply it from our own stock and processing warehouse, and by mill order from major producers such as TISCO and Baosteel Stainless, for which we act as a sales agent. Stock plate ships in about 1–2 weeks after cutting; mill orders typically take 30–60 days depending on thickness and rolling schedule.

Every plate is traceable to its heat number, and copies of the mill certificates stay on file for repeat orders and audits. The same mills also supply our ASTM A240, ASME SA240, JIS G4305 and AISI plate ranges, so mixed-standard orders can ship together.

• Mill-direct prices with our own export documentation
• Own processing warehouse: cutting, bevelling, polishing, PVC film
• PMI and dimensional check before packing
• Mixed-grade shipments across our AISI stainless and GB/T plate ranges
• Technical answers from people who read the standard, not just the price list

SHH STEEL has exported stainless and carbon steel plate to buyers in Asia, the Middle East, Africa, Europe and the Americas.

GB/T 4237 06Cr25Ni20 (S31008) is a heat-resistant austenitic plate grade, known internationally as 310S. It is defined by Table 15 chemistry (C ≤ 0.08, Cr 24.00 – 26.00, Ni 19.00 – 22.00) and Table 20 properties of at least 205 MPa proof strength and 515 MPa tensile strength. Typical uses include furnace muffles, retorts and radiant tubes, heat treatment baskets and conveyor parts and burners, kilns and incinerator parts. 310S is weak in sulfidizing atmospheres because of its high nickel; choose a high-Cr low-Ni option or aluminized parts there.

Before ordering, state the standard edition, the grade name with its code, and any extra tests, so that the mill certificate matches your design documents. SHH STEEL supplies 06Cr25Ni20 plate from stock and by mill order, cut to size and finished in our own warehouse, with EN 10204 3.1 certificates. For related grades see GB/T 4237 06Cr23Ni13 S30908 and GB/T 4237 08Cr21Ni11Si2CeN S30859, our GB/T 4237 category and the ASTM A240 Type 310S page. Send your sizes and quantities for a quotation.