Key Feature

The Low-Carbon Welding-Grade Bar Stock. Maximum 0.03% carbon prevents sensitization in welded structures, ensuring maintained corrosion resistance in heat-affected zones.

Essential for welded components and assemblies where post-weld heat treatment is impractical or impossible.

Common Designations

UNS S30403
AISI 304L
ASTM A276 (Stainless Steel Bars)
ASTM A479 (Bars for Pressure Vessels)
EN 1.4307, X2CrNi18-9
JIS SUS304L

ASTM A276 Grade 304L is the primary specification for general bar applications.

Chemical Composition (Typical wt.%)

C: ≤ 0.030Cr: 18.0 - 20.0
Ni: 8.0 - 12.0
Mn: ≤ 2.00
Si: ≤ 1.00
P: ≤ 0.045
S: ≤ 0.030

Ultra-low carbon (≤0.03%) is the defining characteristic versus standard 304 (≤0.08%).

Mechanical Properties

Tensile Strength: ≥ 485 MPa
Yield Strength: ≥ 170 MPa
Elongation: ≥ 40%
Hardness: ≤ 201 HB
Machinability: Similar to 304

Slightly lower yield strength than standard 304, but adequate for most applications.

Physical Properties

Density: 7.93 g/cm³
Melting Range: 1399 - 1454 °C
Thermal Expansion: 17.2 × 10⁻⁶/K (20-100°C)
Thermal Conductivity: 16.2 W/m·K (100°C)
Non-magnetic when annealed

Identical physical properties to standard 304 stainless steel.

Available Forms

Rounds: 3mm - 600mm diameter
Squares: 3mm - 300mm
Hexagons: 3mm - 100mm
Flats: Various thicknesses and widths
Special Shapes: Custom profiles as required

Comprehensive size range matching standard 304 availability.

Surface Conditions

Hot Finished: Mill scale surface
Cold Finished: Bright, smooth surface
Centerless Ground: Precision dimensions
Polished: Various polish grades
Peeled/Turned: Improved machinability

Various surface finishes available for different application requirements.

Corrosion Resistance

Excellent general corrosion resistance identical to 304. Superior resistance to intergranular corrosion in welded conditions and after exposure to sensitizing temperatures.

Maintains full corrosion resistance in weld heat-affected zones—critical advantage over standard 304.

Temperature Limits

Continuous Service: Up to 425°C (for corrosion resistance)
Higher Temp Service: Up to 870°C with possible sensitization
Cryogenic Service: Excellent down to -196°C

Lower maximum temperature for corrosion service than 304, but better weld performance.

Welding Advantages

• No Sensitization in weld HAZ
• No Post-Weld Annealing required
• Maintains Corrosion Resistance• Suitable for Heavy Sections• All Welding Methods applicable

Eliminates need for costly post-weld heat treatment in most applications.

Key Standards

ASTM A276 304L: Stainless Steel Bars
ASTM A479 304L: Bars for Pressure Vessels
ASTM A484: General Requirements
EN 10088-3: Stainless Steel Bars
JIS G4303: Stainless Steel Bars
ASME SA479: Code Construction

ASME Boiler and Pressure Vessel Code acceptance for critical applications.

Common Applications

• Welded Fabrications: Chemical tanks, pressure vessels, structural frames
• Machined Components: Valve bodies, pump parts, fittings requiring welding
• Food & Beverage Equipment: Welded processing machinery, tanks, conveyors
• Pharmaceutical: Welded process equipment, tanks, machinery components
• Architectural: Welded structural elements, handrails, decorative features
• Chemical Processing: Reactor components, heat exchangers, agitators
• Oil & Gas: Wellhead components, Christmas tree parts, flow control equipment

Specifically selected where welding integrity and maintained corrosion resistance are critical.