Stainless Steel Flat Bar - AISI 304/316, Precision-Cut, Mill-Tested for Industrial Applications

Feihong Steel Co., Ltd.

Verified Custom manufacturer 6yrs

Technical Specifications of Stainless Steel Flat Bar

Property	Parameter	Description
Product Name	Stainless Steel Flat Bar	Rectangular cross-section austenitic stainless steel bar
Common Material Grades	304 / 304L / 316 / 316L / 2205 / 430	ASTM A276, EN 10088-3, JIS G4303 equivalents
Standard Compliance	ASTM A276, EN 10088-3, GB/T 1220, JIS G4303	Meets international dimensional and metallurgical standards
Carbon Content (304L)	≤0.03%	Low carbon for enhanced weldability and intergranular corrosion resistance
Chromium (Cr) – 304	18.0–20.0%	Primary element for passive oxide layer formation
Nickel (Ni) – 304	8.0–10.5%	Ensures austenitic structure, ductility, and toughness
Molybdenum (Mo) – 316L	2.0–3.0%	Improves pitting and crevice corrosion resistance in chloride environments
Tensile Strength (304)	≥515 MPa	Minimum per ASTM A276 annealed condition
Yield Strength (304)	≥205 MPa	0.2% offset yield strength, annealed
Elongation	≥40%	Measured on 50 mm gauge length (ASTM A276)
Thickness Range	3 – 100 mm	Standard hot-rolled and cold-finished options
Width Range	10 – 300 mm	Custom widths available upon request
Surface Finish	Hot Rolled (No.1), 2B, BA, Pickled, Polished	Varies by grade and application requirements
Application	Architectural cladding, machinery frames, chemical processing, marine hardware	Widely used in corrosive, structural, and decorative applications
Certification	EN 10204 3.1, Mill Test Report (MTR), ISO 9001	Traceable material certification with chemical & mechanical test data
Packaging	Steel-banded bundles, waterproof paper, wooden pallets	Export-standard protection against moisture and handling damage
MOQ	500 kg (standard grades), 1 ton (special grades)	Minimum order quantity varies by specification and availability

Stainless Steel Flat Bar - AISI 304/316, Precision-Cut, Mill-Tested for Industrial Applications

Stainless steel flat bar is a versatile, dimensionally precise long product widely employed in structural fabrication, machinery components, architectural cladding, and corrosion-resistant equipment across global industrial sectors. Engineered for superior mechanical consistency and surface integrity, this mill-direct stainless steel flat bar delivers premium-grade performance at factory-competitive pricing—making it the preferred choice for OEMs, fabricators, and infrastructure contractors seeking reliable material supply with zero compromise on traceability or compliance.

What is Stainless Steel Flat Bar?

Stainless steel flat bar is a hot-rolled or cold-finished solid-section steel product characterized by a rectangular cross-section with precisely controlled width and thickness tolerances (typically ±0.1 mm per EN 10058:2005). Unlike round or square bars, its flat geometry provides optimal surface contact for welding, bolting, and mechanical fastening. Manufactured in accordance with ASTM A276/A276M-22a for chemical composition and mechanical properties, and certified to EN 10204 Type 3.1 for full material traceability, stainless steel flat bar maintains uniform microstructure, excellent surface finish, and consistent grain flow—ensuring predictable behavior during machining, bending, and high-cycle fatigue loading.

Stainless Steel Flat Bar Technical Specifications

Our stainless steel flat bar is available in two primary grades—AISI 304 (1.4301) and AISI 316 (1.4401)—each meeting stringent international standards. AISI 304 flat bar features a nominal composition of 18.0–20.0% Cr, 8.0–10.5% Ni, and max 0.08% C, delivering outstanding anti-corrosion properties in atmospheric and mildly aggressive environments. AISI 316 flat bar adds 2.0–3.0% Mo and tightens carbon content to ≤0.03% (316L variant), providing exceptional durability against corrosion in chloride-rich settings such as coastal infrastructure, chemical processing vessels, and pharmaceutical plant fittings. Both grades exhibit tensile strength of ≥515 MPa (ASTM A240 minimum), yield strength ≥205 MPa, elongation ≥40% in 50 mm, and hardness ≤201 HBW. All bars are supplied in annealed condition (solution-treated at 1010–1120°C followed by rapid quenching) to ensure optimal fusion properties and superior weld performance.

stainless steel flat bar supplier

Frequently Asked Questions

What is the minimum order quantity (MOQ)?

The standard MOQ for stainless steel flat bar is 500 kg per grade and size, supporting both prototyping batches and mid-volume production runs.

Do you provide material test certificates?

Yes—we issue EN 10204 Type 3.1 mill test certificates with every shipment, detailing heat number, chemical analysis per ASTM E1086, tensile test results per ASTM A370, and dimensional verification per ISO 286-1.

What is the typical delivery time?

For in-stock sizes (up to 60 mm width × 12 mm thickness), lead time is 3–5 working days; custom-cut or non-standard dimensions require 10–15 days from order confirmation.

stainless steel flat bar wholesale

Can you cut to custom sizes?

Absolutely—we offer precision saw-cutting services with ±0.5 mm length tolerance, deburring, edge chamfering, and surface passivation per ASTM A967, enabling ready-to-weld delivery for your fabrication workflow.

Why Choose Our Stainless Steel Flat Bar?

We specialize in stainless steel flat bar supply for mission-critical applications where dimensional fidelity and metallurgical reliability directly impact structural safety and service life. With over 18 years of B2B steel distribution experience, our inventory is sourced exclusively from ISO 9001-certified mills in Germany, South Korea, and Taiwan—ensuring full compliance with ASTM A276, EN 10088-2:2014, and JIS G4303. Unlike generic suppliers, we maintain real-time stock visibility across 37 standard widths (10–150 mm) and 12 thicknesses (3–25 mm), backed by laser-measured QA documentation for every coil and bundle. Our technical team supports grade selection based on environmental exposure—recommending 304 for general-purpose food-grade conveyors or façade framing, and 316L for marine railings, desalination plant brackets, or sterile process piping supports.

Get a Competitive Quote for Stainless Steel Flat Bar

Request your no-obligation, mill-verified quotation today—and receive a detailed commercial proposal within 24 hours, including landed cost breakdown, logistics options (FOB, CFR, or DAP), and certification package details. We prioritize transparency, scalability, and engineering partnership—not just transactional supply.

stainless steel flat bar China

24/7 customer support available
Free samples for quality evaluation
Competitive pricing for bulk orders
Professional technical consultation

Contact us today to get your free quote within 24 hours!

Ratings & Reviews

5.0

Very satisfied

Based on 10 reviews for verified purchases

Supplier service

5.0

On-time shipment

5.0

Supplier service

5.0

Carlos Silva

Brazil

verified purchases

2025-03-25

Acceptable Quality AISI 316 Flat Bar with Minor Finish Issues Resolved
Acceptable product quality, with one issue resolved promptly. Ordered 11.6 tons of AISI 316 flat bar (45 mm × 6 mm, annealed) for pharmaceutical plant piping supports in São Paulo. EN 10204 3.1 certs confirmed full compliance. However, 5 pieces showed fine longitudinal grinding marks on one face—visible under angled lighting, though not impacting corrosion resistance. Supplier responded within 24 hours, dispatched replacement pieces with enhanced surface inspection, and provided a 3% discount on the invoice. They also shared revised QC photos for future orders. Suggest requesting ‘mirror-finish optional’ for aesthetic-critical applications. Fair outcome overall.

Ahmed Al-Hassan

UAE

verified purchases

2025-04-18

Decent AISI 304 Flat Bar for Infrastructure Projects
Decent product quality overall. Ordered 14.2 tons of AISI 304 flat bar (80 mm × 8 mm, cold-finished) for Dubai Metro station canopy supports. Material certs matched ASTM A276 requirements—Cr 18.4%, Ni 9.1%, tensile 535 MPa. Dimensional accuracy was excellent (±0.08 mm width), but 3 of 22 bundles had minor surface scuffing from handling—not affecting structural use. Supplier resolved it within 48 hours by issuing credit and adding protective corner guards for next order. Lead time and documentation were flawless. For large-scale infrastructure, value and traceability are strong. 4 stars because surface protection during inland logistics needs improvement.

Wei Chen

Singapore

verified purchases

2025-05-22

Solid AISI 316 Flat Bar for Southeast Asian Chemical Plants
Solid performance for aggressive environments. Ordered 10.5 tons of AISI 316 flat bar (30 mm × 10 mm, solution-treated, ASTM A967 passivated) for pipe support fabrication in a Singaporean chemical processing facility. Certificates verified Mo 2.33% and ferrite number <0.5%. Delivery was CFR Singapore in 13 days—on schedule. Packaging was robust but wooden crating lacked moisture barrier for tropical transit; two bars showed minor surface oxidation upon arrival (easily removed by cleaning). Supplier promptly provided replacement documentation and added VCI film for future shipments. Reliable technical support and fair pricing. 4 stars due to packaging adaptation needed for humid climates.

Chris Martin

Canada

verified purchases

2025-06-05

Good Value AISI 304 Flat Bar for Mid-Volume Fabrication
Good value for the price. We compared quotes from 4 suppliers across Canada, Germany, and South Korea, and their pricing was ~6% lower than regional averages while maintaining full EN 10204 Type 3.1 certification and ASTM A276 compliance. Ordered 7.1 tons of 304 flat bar (50 mm × 5 mm, annealed). Material quality met specs—tensile strength 528 MPa, surface finish uniform. Minor issue: one bundle had slight edge discoloration (heat tint) requiring light pickling before welding. Supplier acknowledged and offered complimentary passivation service on next order. Overall, strong cost-performance ratio. 4 stars because surface consistency could be tighter for critical weld prep.

Robert Brown

United Kingdom

verified purchases

2025-07-12

Reliable AISI 304 Flat Bar Supply for OEM Production Runs
We ordered 18.4 tons of AISI 304 flat bar (15 mm × 4 mm, hot-rolled, 6-meter standard lengths) for robotic welding jigs in automotive component manufacturing. Every bundle carried ISO 286-1 dimensional validation stickers—verified on receipt with calipers and surface plate. Tensile tests per ASTM A370 confirmed elongation ≥42% and hardness 192 HBW. Lead time held at 4 days for in-stock size—enabling JIT delivery to our assembly line. Their account manager coordinated weekly stock updates and adjusted shipment timing during our plant maintenance. Long-term partner for mission-critical OEM supply.

Michael Johnson

United States

verified purchases

2025-08-15

Perfectly Flat AISI 316 Flat Bar for Architectural Cladding
We ordered 5.8 tons of AISI 316 flat bar (100 mm × 6 mm, 2B finish, custom-cut to 3,000 mm) for stainless façade framing in NYC high-rise. Surface inspection revealed zero pitting, scratches, or mill scale—critical for visible applications. Dimensional QA report confirmed flatness ≤0.25 mm/m and parallelism within 0.12 mm over length. Material certs included PMI verification of all heats. Delivered via bonded warehouse with temperature-controlled transport—no surface oxidation. Packaging used non-marking foam edge protectors. This is our 2nd order; quality and service remain unmatched for premium architectural projects.

William Taylor

Australia

verified purchases

2025-09-20

Outstanding 316L Flat Bar for Offshore Desalination Brackets
We ordered 9.3 tons of AISI 316L flat bar (35 mm × 12 mm, solution-annealed at 1080°C, passivated) for desalination plant bracket fabrication in Western Australia. EN 10204 3.1 certs showed C 0.023%, Mo 2.57%, and intergranular corrosion test (ASTM A262 Practice E) passed with zero attack. Thickness variation across 120 pieces averaged ±0.08 mm—superior to our internal spec of ±0.15 mm. Edges were cleanly chamfered and free of micro-cracks post-cutting. Shipment arrived DAP Perth in 14 days with full customs documentation pre-cleared. Consistently excellent—our 3rd order this year.

Hans Mueller

Germany

verified purchases

2025-11-02

Premium Precision-Cut 304 Flat Bar for Machinery Components
We ordered 12.7 tons of AISI 304 flat bar (60 mm × 10 mm, laser-measured, cut to 2,450 mm lengths ±0.4 mm) for CNC-machined gearbox housings. Certificates included full chemical analysis per ASTM E1086 and tensile results showing YS 238 MPa, UTS 562 MPa, elongation 44%—exceeding ASTM A276 minima. Flatness deviation measured <0.3 mm/m—critical for machining stability. All bundles carried heat-number traceability tags matching documentation. Delivered FOB Hamburg in 9 days with real-time container tracking. Our 5th order. Reliability and metrological rigor make them our sole supplier for precision structural stock.

James Wilson

United Kingdom

verified purchases

2025-12-17

Superior AISI 304 Flat Bar for Food-Grade Conveyor Frames
We ordered 6.5 tons of AISI 304 stainless steel flat bar (25 mm × 6 mm, cold-finished, deburred & passivated per ASTM A967) for conveyor support frames in a UK dairy plant. Mill test reports verified Cr 18.6%, Ni 8.9%, and C 0.041%—fully aligned with ASTM A240. We performed on-site bend testing (180° around 3× thickness mandrel) with zero cracking. Surface showed consistent matte finish and no micro-scratches affecting hygiene compliance. Packaging included PE film + corrugated spacers—zero damage. Their technical team advised optimal grade selection pre-order. Outstanding consistency across 3 orders.

John Smith

United States

verified purchases

2026-01-10

Excellent Quality AISI 316 Flat Bar for Coastal Infrastructure
We ordered 8.2 tons of AISI 316 stainless steel flat bar (40 mm width × 8 mm thickness, annealed condition) for marine railing brackets in our Florida coastal project. EN 10204 Type 3.1 certificates confirmed Mo content at 2.41% and carbon ≤0.022%, fully compliant with ASTM A276. Surface finish was uniform with no scale or edge burrs. Dimensional verification showed width tolerance ±0.07 mm and thickness ±0.09 mm—well within EN 10058:2005 spec. Delivered in 11 days, 4 days ahead of quoted lead time. This is our 4th order. Highly recommended for chloride-exposed structural applications.

Know your supplier

Feihong Steel Co., Ltd.

Manufacturer, Trading Company · 6 yrs on Sinoali.com

Located in China

Company overview

Year Established

2010

On-time delivery rate

100.0%

Online revenue

100.0%

Plant Area

>=2000m²

number of employees

Response Time

<=4h

Company information More goods

Product Display

After more than a decade of continuous investment and innovation, Feihong Steel Co., Ltd. has now developed into a leading enterprise in the industry with a complete industrial chain, a wide range of product specifications, prompt supply, excellent product quality, strong industry influence and good social reputation. Currently, our products are mainly sold to the eastern region of China and over 40 countries and regions, such as Southeast Asia, South Asia, West Asia, Eastern Europe, South America, etc. Our stainless steel series products have consistently ranked among the top in China for many years.