A106 Gr.B
ASTM A106
A106 Gr.B is a pipeline steel (Pipe family) to ASTM A106. It has a specified 0.2 % proof stress of 240 MPa and a typical tensile strength of about 415 MPa, with a uniform elongation of 22 %. Nominal carbon content is around 0.30 %. For nonlinear FEA, a bilinear model uses E = 210 GPa up to yield and a tangent modulus of 807 MPa above it. It is a general-purpose wrought steel selected on strength, cost and availability.
Bilinear material model — nonlinear FEA
Uniform elongation εu = 22.0% · conservative analysis limit ½εu = 11.0%
Bilinear (BISO) approximation. Elastic modulus E up to the 0.2% proof stress R_p0.2, then a single tangent slope Eₜ to the ultimate tensile strength: Eₜ = (Rₘ − R_p0.2) / (εu − R_p0.2/E − 0.002), where εu is the uniform elongation and Rₘ is a typical (nominal) UTS within the specified band. The half-εu figure is a conservative strain limit for the analysis. Treat these as guidance for first-pass models; for critical work use a measured true stress–strain curve for the actual product and condition.
Ratings — engineering judgement
Weldabilitymoderate
Medium carbon (~0.30%) — preheat and hydrogen-controlled consumables advisable, especially in thicker sections.
Machinabilitygood
Machines well, particularly in the normalised or pre-tempered condition.
Corrosion resistancepoor
No inherent corrosion resistance — protect by paint, galvanising or plating in exposed use.
Hardenabilitygood
Responds well to quench-and-temper (and, for the case-hardening/nitriding grades, to surface treatment).
Toughnessmoderate
Adequate toughness for general use at ambient temperature.
Indicative ratings derived from composition and family — engineering guidance, not specification values.
Physical properties
| Density | 7850 | kg/m³ |
| Elastic modulus | 210 | GPa |
| Shear modulus | 80.8 | GPa |
| Poisson's ratio | 0.30 | |
| Thermal expansion | 12.0 | ×10⁻⁶/°C |
| Thermal conductivity | 48 | W/(m·K) |
| Specific heat | 470 | J/(kg·K) |
| Magnetic | Yes |
Typical values for astm pipe steel — use the mill certificate for the specific product.
Chemical composition (wt %)
Typical composition per ASTM A106.
Available forms
Common applications
- Oil and gas transmission line pipe
- Water and slurry pipelines
- Structural and pressure piping
History
The ASTM pipe steels cover general and pressure piping (A53/A106 carbon), low-temperature service (A333) and high-temperature Cr-Mo alloy pipe (A335) — the plumbing of process and power plant.
- 1926ASTM A53/A106 standardise welded and seamless carbon steel pipe
- 1950ASTM A335 Cr-Mo alloy pipe adopted for high-temperature steam lines
This profile is generated from the grade's core data and family. Composition is decoded from the designation where its naming system defines it; physical properties are family-typical and ratings are indicative. Confirm critical values against the governing standard or the mill certificate. Equivalents, historical designations and hand-written expert notes are added per grade over time.