Key Feature

The Nickel-Free Economical Piping Solution. Provides stainless steel appearance and basic corrosion resistance without nickel, offering significant cost savings over 304 stainless steel pipe.

The most economical chromium stainless steel pipe for general-purpose applications.

Common Designations

UNS S43000
AISI 430
ASTM A268 TP430 (Seamless Ferritic Pipe)
ASTM A554 (Welded Mechanical Tubing)
EN 1.4016, X6Cr17
JIS SUS430

ASTM A268 is the primary specification for ferritic stainless steel pressure pipe.

Chemical Composition (Typical wt.%)

C: ≤ 0.12
Cr: 16.0 - 18.0Mn: ≤ 1.00
Si: ≤ 1.00
Ni: ≤ 0.75 (residual)
P: ≤ 0.040
S: ≤ 0.030

No intentional nickel addition distinguishes it from austenitic grades and controls cost.

Mechanical Properties

Tensile Strength: ≥ 450 MPa
Yield Strength: ≥ 310 MPa
Elongation: ≥ 20%
Hardness: ≤ 183 HB

Good ductility for forming; lower elongation than austenitic grades but adequate for most applications.

Physical Properties

Density: 7.70 g/cm³
Melting Range: 1425 - 1510 °C
Thermal Expansion: 10.4 × 10⁻⁶/K (20-100°C)
Thermal Conductivity: 26.0 W/m·K (100°C)
Strongly magnetic

Lower thermal expansion than austenitics (304: 17.2 × 10⁻⁶/K) - advantageous for thermal cycling applications.

Pressure Ratings

Schedule 10/40: Standard piping
ASME B31.3 compliance
Lower than 304 for same schedule

Pressure ratings generally lower than austenitic grades due to different mechanical properties.

Heat Treatment

Not hardenable by heat treatmentAnnealing: 790-850°C, air or slow cool
Stress Relief: 650-760°C
Maximum Service Temperature: 815°C

Can only be strengthened by cold working; limited high-temperature capability due to 475°C embrittlement risk.

Corrosion Resistance

Good resistance to atmospheric corrosion, nitric acid, organic acids, and fresh water. Poor resistance to chlorides and reducing acids.

Suitable for indoor and mild outdoor applications; not recommended for marine or de-icing salt environments.

Welding Characteristics

Limited weldability
Grain growth in HAZ
Reduced ductility in welds
Post-weld annealing recommended
Matching filler metals essential

More challenging to weld than austenitic grades; requires careful procedure control.

Key Standards

ASTM A268 TP430: Seamless Ferritic Pipe
ASTM A554: Welded Mechanical Tubing
ASTM A791: Welded Ferritic Pipe
EN 10216-5: Seamless Pressure Tubes
JIS G3463: Stainless Steel Pipe

Widely available in various finishes and applications.

Common Applications

• Automotive Exhaust Systems: Muffler shells, tailpipe extensions, resonator bodies
• Appliance Components: Dishwasher drain pipes, washing machine tubs, range hood ducts
• Architectural Piping: Handrails, guardrails, decorative columns (indoor)
• Heat Exchangers: Automotive radiator tubes, heater cores (certain media)
• Food Service: Sink drains, kitchen exhaust ducts (non-critical)
• Industrial: Ventilation ducting, fume exhaust stacks (mild conditions)
• Furniture: Outdoor furniture frames, display system structures

Cost-effective choice where appearance and moderate corrosion resistance suffice.