ASTM A203 Grade B is a nickel-alloy pressure vessel steel designed for welded equipment operating in low-temperature environments. With its 3.5% Ni composition, A203 Gr.B delivers excellent toughness, stable weldability, and reliable strength retention under sub-zero service conditions. It is widely used in LNG storage tanks, cryogenic vessels, gas separation units, and other applications requiring dependable low-temperature performance and long-term structural integrity.
Chemical Composition

C	Mn	P	S	Si	Ni
≤0.17	0.40–0.70	≤0.025	≤ 0.025	0.15–0.30	3.25–3.75

 
Mechanical Properties

Property	Yield Strength	Tensile Strength	Elongation	Impact Energy
Requirement	≥ 250 MPa	485–620MPa	≥ 22%	Excellent low-temperature performance (per ASTM A203 requirements)

 
Dimensions

Thickness	3–150 mm
Width	1220–4200 mm
Length	5000–18000 mm
Supports custom cutting and shaping.

  
Stock & Processing
Regular stock for A203 Grade B
Cutting, drilling, welding, bending, machining
Custom dimensions available
Fast delivery for project orders
Global supply capability
 
Applications
LNG storage tanks
Low-temperature pressure vessels
Cryogenic process equipment
Gas separation and refrigeration units
Welded components requiring nickel-alloy toughness
 
Certification & Support
Complies with ASTM A203/A203M
EN 10204 3.1 / 3.2 available
Third-party inspection: BV / LR / ABS / DNV / SGS
Technical support for material selection and fabrication