JIS G4305 SUS 409L Cold Rolled Stainless Steel Coil Supplier

SUS409L Cold Rolled Stainless Steel Coil & Sheet | JIS G4305 SUS 409L Stainless Steel Strip Manufacturer & Exporter – Gangsteel

Gangsteel is a premier manufacturer and global exporter specializing in high-performance ferritic stainless steel products. Our JIS G4305 SUS409L cold rolled stainless steel coils, sheets, and strips represent one of the most cost-effective and reliable solutions for high-temperature, mildly corrosive environments. As a titanium-stabilized, ultra-low-carbon grade (also known as Grade 409L or UNS S40903), SUS409L delivers excellent oxidation resistance up to 800°C, superior weldability, outstanding formability, and magnetic properties at a fraction of the cost of austenitic grades.

Produced exclusively via cold rolling for precision surface quality and tight tolerances, our SUS409L meets or exceeds JIS G4305 (Cold-rolled stainless steel plate, sheet and strip) requirements. Equivalent to ASTM A240 Type 409L, EN 1.4512, and GB 022Cr11Ti, Gangsteel's material is widely used in automotive exhaust systems, heat shields, catalytic converter shells, agricultural equipment, and industrial flue components worldwide.

This detailed product introduction covers every key aspect of our JIS G4305 SUS409L cold rolled stainless steel — from specifications and properties (presented in tables) to manufacturing, applications, advantages, and why Gangsteel is your trusted single-source partner.

Introduction to SUS409L Stainless Steel

SUS409L is a titanium-stabilized ferritic stainless steel developed specifically for automotive exhaust and high-temperature applications. The "L" designation indicates its ultra-low carbon content (≤0.030%), which dramatically improves weldability and eliminates sensitization risk in the heat-affected zone. With 10.5–11.7% chromium and controlled titanium addition (Ti ≥ 6 × (C + N)), it forms a stable protective oxide layer that resists exhaust gas corrosion and scaling up to 800°C while maintaining excellent formability comparable to mild steel.

Non-hardenable by heat treatment and magnetic in all conditions, SUS409L bridges the performance gap between ordinary carbon steel and expensive austenitic grades like SUS304. Gangsteel focuses on cold rolled SUS409L, delivering superior surface quality, precise thickness control, and consistent mechanical properties optimized for deep drawing, stamping, roll forming, and robotic welding in high-volume production lines.

Chemical Composition of JIS G4305 SUS409L

Chemical Composition Table

Gangsteel's heats are tightly controlled at the lower end of carbon and optimal titanium levels for maximum weld performance and formability. Full ladle analysis and EN 10204 3.1 certification are standard for every coil.

Mechanical Properties

In annealed condition per JIS G4305:

Mechanical Properties Table (Annealed)

SUS409L maintains ductility across a wide temperature range, allowing severe forming without intermediate annealing in many cases.

Physical Properties

Physical Properties Table

These properties ensure excellent thermal cycling resistance in exhaust and heat-exchanger applications.

Equivalent Materials Comparison

Equivalent Materials Comparison Table

SUS409L offers superior weld performance over standard SUS409 due to lower carbon.

Manufacturing Process: Cold Rolled at Gangsteel

Gangsteel's cold rolling process for SUS409L starts with hot-rolled coils that undergo full solution annealing at 800–900°C, followed by pickling and multiple precision passes through Sendzimir or 20-high mills. Final bright annealing or skin pass produces uniform 2B or 2D finishes with excellent surface quality. Thickness range: 0.3–3.0 mm. Width: 600–1524 mm. In-line eddy current testing and gauge control guarantee zero defects.

Finishes available: 2B (standard matte), 2D (dull), BA (bright annealed), No.4/HL (brushed). Protective PVC/PE film and custom slitting are standard services.

Available Forms, Sizes, and Specifications

• Cold rolled coils: 0.3–3.0 mm thick, up to 1524 mm wide
• Cold rolled sheets: Cut-to-length up to 6000 mm
• Strips: Narrow widths from 10 mm

All material complies with JIS G4305; optional ASTM A240, EN 10088-2, and customer-specific requirements. Tolerances per JIS or tighter upon request.

Key Applications of SUS409L Cold Rolled Products

SUS409L dominates in high-temperature, mildly corrosive environments:

Automotive Exhaust Systems

• Muffler shells, catalytic converter casings, downpipes
• Heat shields, exhaust manifolds

Industrial and Agricultural

• Furnace tubing, heat exchanger components
• Tractor exhaust, fertilizer equipment parts

Other Uses

• Flue pipes, transformer cases, fuel filter housings
• Drainage structures in mild corrosive conditions

Its oxidation resistance and low cost make it the material of choice over coated carbon steel.

Advantages of Choosing SUS409L Stainless Steel

• Cost-effective alternative to austenitic grades
• Excellent high-temperature oxidation resistance up to 800°C
• Superior weldability (no sensitization in HAZ)
• Outstanding formability comparable to mild steel
• Good corrosion resistance in exhaust condensate
• Magnetic for sensor compatibility
• Fully recyclable with low environmental impact

Compared to standard SUS409, the L-grade provides better long-term durability in welded structures.

Corrosion and Oxidation Resistance

SUS409L forms a tightly adherent chromium oxide scale that protects against internal exhaust condensate (pH 2–4 acids) and external road salt. Cyclic oxidation tests confirm minimal scaling after 1000 hours at 750°C. Salt spray performance far exceeds carbon steel or aluminized coatings.

Weldability and Fabrication

SUS409L supports all conventional welding methods (TIG, MIG, resistance, laser) without preheating or post-weld heat treatment. Titanium stabilization ensures full corrosion resistance in the heat-affected zone. Recommended fillers: 409Cb or ER309 for dissimilar joints. Its formability allows tight-radius bends and deep draws, reducing manufacturing steps.

Why Choose Gangsteel for SUS409L Cold Rolled Coils and Sheets?

• Full cold rolling capability with precision control
• Strict JIS G4305 compliance and batch traceability
• Wide finish and temper options with stock availability
• Competitive pricing and flexible MOQ
• Export expertise to 60+ countries with robust packaging
• Technical support including welding procedures and forming advice
• ISO 9001 certified; third-party inspections (SGS, BV, TUV)

Quality Assurance and Certifications

Every coil undergoes chemical analysis, mechanical testing, surface inspection, and dimensional verification. Material Test Certificates include full traceability. Customer audits and special testing are welcomed.

Packaging, Shipping, and Logistics

Coils are eye-to-sky or eye-to-wall packed on steel/wooden pallets with waterproof wrapping and edge protection. Sheets are bundled with skids. We arrange container, LCL, or break-bulk shipments with full tracking and insurance.

Conclusion: Partner with Gangsteel for Superior SUS409L Performance

SUS409L Cold Rolled Stainless Steel Coil & Sheetfrom Gangsteel, manufactured to JIS G4305, combines technical excellence, economic value, and proven reliability for automotive exhaust and industrial applications. With full cold-rolled production capability, strict quality control, and dedicated customer service, we deliver more than just material — we deliver confidence.

Contact Gangsteel today for competitive quotations, detailed technical data sheets, samples, or custom SUS409L cold rolled stainless steel coils, sheets, and strips. Let us help optimize your next project with reliable, high-performance stainless steel solutions that exceed expectations.