UNS S30403 Stainless Steel – Low-Carbon Weld-Stable Universal Grade

Product Overview

UNS S30403 is the low-carbon derivative of S30400, purpose-built to eliminate intergranular corrosion (sensitization) in welded assemblies. With a maximum carbon content of 0.03%, it prevents chromium carbide precipitation in the heat-affected zone during welding, eliminating the need for post-weld annealing-a critical advantage for complex, large-scale fabrications. This grade retains the full corrosion resistance, formability, and non-magnetic properties of standard 304, while offering enhanced weld integrity and ductility. It is the preferred choice for welded components that require long-term corrosion stability, bridging the gap between performance and fabricability for critical applications.

Chemical Composition (Mass Fraction, %)

C ≤ 0.03, Cr: 18.00-20.00, Ni: 8.00-11.00, Mn ≤ 2.00, Si ≤ 1.00, P ≤ 0.045, S ≤ 0.030, N ≤ 0.11

Mechanical Properties (Annealed Condition)

Tensile Strength ≥ 480 MPa; Yield Strength ≥ 175 MPa; Elongation ≥ 40%; Hardness ≤ 200 HB

Core Advantages

Sensitization-resistant for welded structures; no post-weld heat treatment required; superior intergranular corrosion resistance vs. S30400; retains all general corrosion properties of 304; excellent ductility and weldability; non-magnetic.

Typical Applications

Welded pressure vessels, chemical piping, pharmaceutical equipment, food processing pipelines, large fabricated tanks, and components exposed to corrosive media post-welding.

Equivalent Grades

AISI 304L, EN 1.4307, GB 022Cr19Ni10, SUS304L

Stainless Steel Suppliers

If you have project requirements for stainless steel, we welcome your order. GNEE has a large inventory of popular products for you to choose from. It can be processed into various practical product forms, including plates, coils, tubes, bars, wires, etc. For detailed chemical composition information and free samples, please contact our factory immediately. We offer competitive prices and excellent service.Email: info@gneestainless.com

 

Testing and Documentation: Factory test certificate, EN 10204 3.1, chemical report, mechanical report, destructive testing report, non-destructive testing report, PMI test report, visual inspection report, third-party inspection report, NABL certified laboratory report.
Packaging: Wooden crate packaging, bubble wrap packaging, steel strapping, or packaging according to customer requirements.