We estimate that ASTM 347 stainless steel plate wholesale prices in 2025 typically range from USD 1.8–4.5 per kg (≈ USD 1,800–4,500 per metric ton) depending on region, mill-finish, and order scale — with China-origin export offers clustering near the low end (~USD 2–4/kg) and European/US finished plates and service-center stocked pieces frequently priced above USD 3.5–5.0/kg at the retail level. These spreads are driven mainly by nickel and chromium feedstock costs, alloy surcharges, freight and logistics, and whether the product is 347 or the higher-carbon 347H.
What is ASTM 347
ASTM 347 is not a separate ASTM grade name; in plate/sheet form the material is normally supplied to ASTM A240 / A240M chemistry and mechanical requirements as “Type 347” (UNS S34700, sometimes JIS SUS347). It’s an austenitic, niobium-(columbium) stabilized stainless steel optimized to resist intergranular carbide precipitation and retain strength in intermittent high-temperature service.
Mechanical and corrosion characteristics
We summarize the key technical points buyers need:
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Microstructure & stabilization: niobium (columbium) ties up carbon and prevents chromium carbide at grain boundaries, improving resistance to intergranular corrosion after welding or exposure in the 427–816°C (800–1500°F) range.
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High-temperature capability: good oxidation and creep resistance up to ~816°C in many service cases (exact limits depend on section thickness and environment).
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Workability: readily formed and cold worked; non-magnetic when annealed; tough at low temperatures.
347 vs 347H — practical choice rules
We prefer 347H when the service involves sustained exposure above ~550°C or when higher creep strength is required, because 347H has a higher carbon specification which increases high-temperature strength. For welded fabrications where post-weld annealing is not feasible, plain 347 (lower carbon) or low-C alternatives (e.g., 347L equivalents or 321 for certain cases) may be better to reduce carbide risk.
Manufacturing forms, common finishes, and sizes
347 plates are produced as hot-rolled plate (HR), cold-rolled sheet (2B, BA), annealed & pickled plate, and sometimes in coil form. Typical thickness ranges for plates are from a few millimetres up to >100 mm for heavy sections; common service-center stocked plate thicknesses are 3–25 mm. Surface finish (No.1 hot-rolled, 2B cold-rolled, NO.8 mirror, etc.) affects both price and downstream fabrication cost.
Standards & quality: what to specify on an order
Specify at minimum:
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ASTM A240 / A240M for plate/sheet.
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UNS number S34700 (or 1.4550 / AISI 347) and whether 347H is required.
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Mill test certificates (chemical & mechanical), heat number traceability, and whether additional testing (UT, PMI, hardness) is required. For pressure or critical applications, request NACE, PED, or other project-specific approvals where relevant. Carpenter and other mill datasheets provide detailed guidance for heat treatment and traceability.
Typical applications (why buyers pay for 347)
We see 347 plate used widely where intermittent high-temperature stability matters: boiler casings, furnace parts, petrochemical process heaters, aircraft/engine components exposed to exhaust heat, and some heavy welded pressure vessel parts. Its stabilized chemistry is the selling point when weld decay or post-fabrication anneals are impractical.
Key factors that determine price in 2025
Price is a compound of many inputs. The most important drivers this year:
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Base metal & alloy feedstock: nickel and chromium account for a large portion of cost. Nickel volatility in 2025 increased plate price sensitivity.
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Alloy surcharges: stainless mills publish monthly alloy surcharge schedules that add to base steel pricing (e.g., Outokumpu surcharge reports).
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Niobium (columbium) and minor elements: while smaller than nickel/chrome, niobium availability and price can affect premium grades.
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Region and trade flows: China export mill prices are often lower than EU/US domestic mill/service-center prices because of labor/factory cost differences and export competition.
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Logistics and freight: ocean freight, insurance, and inland handling since 2020 have had large swings; buyers paying door-delivered costs see these as meaningful line items.
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Order scale, finish & certification: small cut-to-size retail pieces carry a higher per-kg cost than bulk coil or factory pallet lots.
2025 Global Price Comparison (representative ranges)
Notes about the table: these are indicative wholesale/FOB export ranges and sample retail numbers gathered from supplier price pages, marketplace listings, mill/service-center notices, and commodity indices in August 2025. Exact quotes depend on quantity, finish, certificates, and logistics. Sources cited beneath the table.
| Region / Channel | Typical price (USD per kg) | Typical price (USD per metric ton) | Notes / evidence |
|---|---|---|---|
| China — factory export offers (bulk, mill-finish) | USD 1.8 – 4.2 / kg | USD 1,800 – 4,200 / ton | Large-lot Alibaba / Chinese mills list low-end offers near USD 1–4/kg; specific factory quotes show ~USD 4.15/kg for some 347H plates. |
| India — domestic mills / exporters | USD 2.0 – 4.0 / kg | USD 2,000 – 4,000 / ton | Indian exporters and mills generally price slightly above low-cost Chinese mills but below EU mill finished prices. (local supplier listings). |
| Europe — mill & service center (finished, stocked) | USD 3.5 – 6.5 / kg | USD 3,500 – 6,500 / ton | European alloy surcharges + higher production cost; retail/service center stock items can be at the high end. |
| USA — service centers & retail cut pieces | USD 3.0 – 7.0 / kg (retail higher) | USD 3,000 – 7,000 / ton | Retail cut pieces (small sizes) are significantly pricier per kg; mill/large qty orders can align with EU mills. |
| Middle East / Turkey (trading hubs) | USD 2.5 – 5.0 / kg | USD 2,500 – 5,000 / ton | Regional trading hubs price between China and Europe depending on freight & import duties. (supplier & trader listings). |
Interpretation: Chinese mill prices frequently appear at the low end of the global range; however, landed cost to your project location (including duty, inland transport, and inspection) often narrows the gap. Retailized pieces from service centers (cut, edge-worked, certified) substantially raise the per-kg price; compare delivered total cost, not just FOB mill price.
How we collected and validated the pricing data (methodology)
We sampled mill catalogs, service center item pages, and marketplace listings (China factories + Alibaba), cross-checked supplier unit-price lines and recent mill announcements, then aligned the ranges with commodity price trends (LME nickel, ferrochrome indices) and mill surcharge publications to form a defensible band. For near-term feedstock price influence we inspected LME nickel quotes (Aug 2025) and ferrochrome pricing indexes to explain the directional pressure.
Buying & specification checklist (what to ask for in a quote)
To minimize risk and unexpected costs, always request:
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Exact ASTM / UNS designation (e.g., ASTM A240 TP347 / UNS S34700 or 347H).
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Mill Test Certificate (MTC): chemical and mechanical, signed by the mill.
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Heat number traceability and full manufacturing route (HR/CR, anneal, pickling).
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Finish & edge condition (2B, No.1, shot-blasted, sheared edges, saw cut). Finish determines extra processing charges.
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Additional testing: PMI, ultrasonic testing (UT), flattening (for pressure parts) if needed.
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Delivery Incoterm and freight breakdown (FOB, CNF, DDP) — landed cost frequently beats low FOB.
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Quantity discounts and lead-time commitments; ask for alternative nearby stock in case of delays.
Fabrication, storage and welding notes that affect total cost
Small oversights during fabrication can increase the “installed” cost beyond raw material:
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Welding: 347 is chosen to prevent sensitization in the weld-heat-affected zone; careful weld procedure and filler choice still matter to avoid localized issues. Post-weld cleaning/passivation may be needed for corrosion-sensitive applications.
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Cutting & edge work: heavy plate cutting, edge grinding, or thermal cutting add to per-piece cost.
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Storage: long outdoor storage without protective layering elevates pickling/cleaning cost before fabrication.
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Inspection & certification: PMI and full traceability add to cost but are essential for critical sectors (petrochemical, power).
How 347 compares to close alternatives (practical buying view)
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304 / 304L: cheaper, but vulnerable to intergranular attack after welding in the carbide-precipitation range. Use 304 where high-temp stability is not required.
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321: titanium stabilized; similar purpose to 347, sometimes slightly cheaper or more available depending on region. For many welded high-temp cases, 321 is a close substitute.
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316 / 316L: superior chloride resistance; often used instead of 347 when corrosion (not high temp stabilization) is primary. Expect higher price due to molybdenum content.
FAQs
Q1 — What is a realistic lead time for ASTM 347 plate in 2025?
A: For mill stock and bulk orders expect 2–8 weeks depending on finish and certification needs; cut-to-size service center orders can be faster but cost more. If the mill needs to hot-roll and anneal a dedicated lot, add several weeks.
Q2 — Is 347 more expensive than 304 and why?
A: Yes — because of alloying (niobium) and the impact of nickel/chrome content. Also, lower production volumes vs common 300-series grades and occasional surcharge premiums make 347 pricier.
Q3 — Should I buy 347 or 347H for a heat exchanger shell?
A: For sustained high temperature service, we recommend 347H. For intermittent exposure where low carbon is preferred, standard 347 may suffice. Confirm with your design engineer.
Q4 — How much does finish (2B vs No.1) affect price?
A: Surface finish changes rolling and finishing steps; 2B (cold-rolled) is typically more expensive than hot-rolled No.1. For cosmetic/food contact applications, expect a premium for bright finishes.
Q5 — What documentary evidence should I insist on?
A: Mill Test Certificate (EN/ASTM format), heat/lot traceability, and PMI/UT reports if required by your project spec. For pressure-retaining parts, ask for PED / NRCan / NACE documentation as applicable.
