Carbon Steel S420 Round Bar
➡️ CS S240 | EN 1.8902 (S420N) | EN (S420NL)
➡️ ASTM, EN, JIS & International Standards
➡️ Supply Conditions
➡️ Multiple Diameters & Supply Lengths
➡️ Global Export & International Delivery
Country of Origin:
Europe, Japan, USA
Material Type:
Carbon Steel
UNS Number:
-
Wr. No.:
1.8902 (S420N) / 1.8912 (S420NL)
MTC Available:
EN 10204 3.1
Product Description for Carbon Steel S420 Round Bar
Carbon Steel S420 Round Bar is a normalised or normalised rolled weldable fine-grain structural steel bar produced to EN 10025-3, supplied as S420N (1.8902 (S420N)) or as the low-temperature variant S420NL (1.8912 (S420NL)). The designation sets a minimum yield strength of 420 MPa for thicknesses or diameters up to 16 mm, together with normalised or normalised rolled fine-grain quality, requiring 40 J at minus 20 degC for the N variant and 27 J at minus 50 degC for the NL variant.
Strength is developed by grain refinement rather than by high carbon. Aluminium, niobium, vanadium and titanium additions produce fine carbonitrides that restrict austenite grain growth during normalising, raising both yield strength and low-temperature toughness at the same time. Carbon remains capped at 0.20%, so the carbon equivalent stays moderate and the steel remains readily weldable despite its higher strength.
Chemistry is controlled with carbon at 0.20% maximum, manganese at 1.70% maximum, phosphorus at 0.03% maximum and sulphur at 0.03% maximum for the bar sizes normally supplied. With the carbon equivalent capped at 0.48, shielded metal arc, gas metal arc, flux cored and submerged arc welding all work with standard low-hydrogen consumables and normal preheat practice.
Round bars are commonly available from about 8 mm to 250 mm diameter, with dimensional tolerances to EN 10060. Standard random lengths are 6 metres and cut-to-length supply is widely offered. Surface condition is normally hot rolled or hot rolled and descaled, with turned and peeled bar available where a cleaner surface is needed.
Typical applications include structural frameworks, columns, bracing, anchor bolts and tie rods, bridge and crane components, machinery bases and frames, transmission towers, offshore and marine structures, earthmoving and lifting equipment, and general welded fabrication. Industries served include construction and infrastructure, heavy engineering, shipbuilding, offshore oil and gas, mining equipment and material handling.
Common Applications of Carbon Steel S420 Round Bar
➡️ Machined shafts, spindles, valve stems, pump sleeves and pins for food, beverage, dairy and pharmaceutical equipment, where the passive chromium oxide film resists both product acids and caustic clean-in-place chemicals.
➡️ Fasteners, studs, bolts, threaded rod and anchor components produced from bar stock, chosen for corrosion resistance combined with the ductility needed for cold heading and thread rolling.
➡️ Chemical, water treatment and general process plant parts such as agitator shafts, flange blanks, nozzles and support components handling water, steam and mildly corrosive media free of significant chlorides.
➡️ Architectural and structural hardware including handrail stanchions, balustrade fittings, tension rods and bollards, where a bright ground or polished bar finish provides both appearance and low maintenance.
International Equivalent Grade for CS S420 Round Bar
Standard
Country / Region
Grade / Equivalent
EN 10025-3
Europe / EU
S420 (1.8902 (S420N) / 1.8912 (S420NL))
ASTM A572 / A572M
USA
Grade 60 (comparable, not identical)
BS EN 10025-3
United Kingdom
S420N / S420NL
DIN 17102
Germany
StE 420 (superseded)
JIS G3106
Japan
-
GB/T 1591
China
Q420
KS D 3515
South Korea
-
ISO 630-3
International
S420N
Technical Specification for Carbon Steel S420 Round Bar
Specification
Value
Unit
Material
Carbon Steel
-
Grade / Designation
S420 / W.Nr. 1.8902 (S420N) / 1.8912 (S420NL)
-
UNS Number
Not assigned by EN standards
-
Product Form
Round Bar / Rod
-
Governing Chemistry Standard
EN 10025-3
-
Hot-Finished Bar Standard
EN 10025-3 with dimensional tolerances to EN 10060
-
Cold-Finished Bar Standard
Cold finishing not covered by EN 10025-3. Use EN 10277 bright bar where required
-
Dimensional Tolerance Standard
EN 10060 for hot-rolled round bar
-
Diameter (available range)
8 - 250
mm
Length (standard random)
6 (random) or cut to length
m
Manufacturing Process
Hot rolling
-
Production Route
Electric arc furnace or basic oxygen furnace, ladle refined, continuously cast, hot rolled
-
Surface Finish
Hot rolled or hot rolled and descaled. Peeled and turned available on request
-
Heat Treatment / Delivery Condition
Normalised or normalised rolled (+N)
-
Carbon Equivalent CEV (typical, calculated)
0.48 maximum
-
Impact Test Temperature
-20 degC
-
Minimum Impact Energy KV
40
J
Deoxidation / Killing
Fully killed with fine grain practice
-
Density (typical)
7.85 - 7.87
g/cm3
Melting Range (approximate)
1480 - 1526
degC
Thermal Conductivity at 20 degC (typical)
51.9
W/m.K
Coefficient of Thermal Expansion 20-100 degC (typical)
12.2
um/m.K
Specific Heat Capacity (typical)
486
J/kg.K
Electrical Resistivity at 20 degC (typical)
0.159
uOhm.m
Modulus of Elasticity (typical)
200 - 210
GPa
Poisson Ratio (typical)
0.27 - 0.30
-
Magnetic Properties
Ferromagnetic
-
Applicable Testing / Inspection Standard
EN ISO 6892-1 tensile testing and EN ISO 148-1 Charpy V-notch impact testing
-
Certification / Inspection Document
EN 10204 Type 3.1 inspection certificate. Type 3.2 on request
-
Technical Specifications
Get the key technical specifications for Carbon Steel S420 Round Bar
Carbon Steel S420 Round Bar is ordered against EN 10025-3, which is a mechanical performance specification supported by maximum composition limits and a mandatory maximum carbon equivalent. Dimensional tolerances for hot-rolled round bar are taken from EN 10060 rather than from the product standard, and the required tolerance class should be nominated on the order rather than left to mill standard.
The delivery condition is normalised or normalised rolled (+N). This produces a fine, uniform ferrite grain size through the section, which is what delivers both the 420 MPa yield strength and the low-temperature impact toughness. Because the properties depend on that grain structure, hot forming above the normalising temperature or welding at excessive heat input can coarsen the grain and reduce certified toughness. Re-normalising after heavy hot working is recommended.
Impact toughness is the defining feature of the quality suffix. S420 requires a minimum Charpy V-notch energy of 40 J at -20 degC, tested to EN ISO 148-1 on 10 mm by 10 mm specimens. Tensile testing follows EN ISO 6892-1. The tensile strength requirement is a range of 520-680 MPa rather than a minimum, so material that is too strong is also non-conforming.
The maximum carbon equivalent of 0.48 is mandatory and is reported on the certificate. Density is about 7.85 – 7.87 g/cm3, modulus of elasticity is approximately 200 – 210 GPa, thermal conductivity is around 51.9 W/m.K and the material is ferromagnetic. Ultrasonic examination to EN 10308 and surface crack detection can be added by agreement. Material is normally released with an EN 10204 Type 3.1 inspection certificate, with Type 3.2 third-party inspection available on request.
Chemical Composition for Carbon Steel S420 Round Bar
Element
Symbol
Min
Max
Unit
Carbon (diameter up to 16 mm)
C
-
0.20
%
Manganese
Mn
1.00
1.70
%
Silicon
Si
-
0.60
%
Phosphorus
P
-
0.03
%
Sulphur
S
-
0.03
%
Nitrogen
N
-
0.03
%
Copper
Cu
-
0.70
%
Chromium
Cr
-
0.30
%
Nickel
Ni
-
0.80
%
Molybdenum
Mo
-
0.10
%
Vanadium
V
-
0.20
%
Niobium
Nb
-
0.05
%
Titanium
Ti
-
0.05
%
Aluminium total
Al
0.020
-
%
Carbon Equivalent CEV maximum
CEV
-
0.48
%
Chemical Composition
View the chemical composition and applicable material limits for CS S420 Round Bar
EN 10025-3 specifies composition as maximum limits rather than as ranges, because the standard is written around guaranteed mechanical performance and weldability. Carbon is capped at 0.20% for the bar sizes normally supplied, and the limit rises slightly for very heavy sections. Keeping carbon low is what preserves field weldability at this strength level.
Manganese up to 1.70% is the principal strengthening and hardenability element and combines with sulphur to prevent hot shortness during rolling. Silicon acts as a deoxidiser and adds modest solid-solution strengthening. Phosphorus and sulphur are each limited to 0.03%, which is tightened relative to the JR quality class to support the lower impact test temperature.
Aluminium is specified at a minimum of 0.020% total, and niobium, vanadium and titanium are permitted up to 0.05%, 0.20% and 0.05% respectively. These are the microalloying elements that do the real work here. They form fine carbonitrides that pin austenite grain boundaries during normalising, producing a fine ferrite grain size that raises yield strength and low-temperature toughness simultaneously. Residual chromium, nickel, molybdenum and copper are limited to 0.30%, 0.80%, 0.10% and 0.70%.
The maximum carbon equivalent of 0.48, calculated by the IIW formula CEV equals C plus Mn/6 plus (Cr+Mo+V)/5 plus (Ni+Cu)/15, is a mandatory requirement of the standard and is reported on the mill certificate. It is the value the fabricator uses to establish preheat temperature and welding procedure.
Mechanical Properties for Carbon Steel S420 Round Bar
Mechanical Property
Value
Unit
Yield Strength ReH minimum, diameter up to 16 mm
420
MPa
Yield Strength ReH minimum, diameter over 16 up to 40 mm
410
MPa
Tensile Strength Rm, diameter up to 16 mm
520 - 680
MPa
Elongation A minimum, longitudinal
19
%
Charpy V-notch Impact Energy KV minimum
40
J
Charpy Impact Test Temperature
-20
degC
Carbon Equivalent CEV maximum
0.48
-
Hardness typical
Not specified by the standard
-
Modulus of Elasticity typical
200 - 210
GPa
Shear Modulus typical
79 - 81
GPa
Mechanical Properties
Check the key mechanical properties and performance requirements of CS S420 Round Bar
EN 10025-3 makes yield strength, tensile strength, elongation and impact energy mandatory acceptance criteria. For S420 the minimum yield strength is 420 MPa for diameters up to 16 mm, with the tensile strength required to fall within the band 520-680 MPa. Minimum longitudinal elongation is 19%.
Yield strength is specified against nominal thickness or diameter and reduces in defined steps as section size increases, because thicker product cools more slowly from the rolling temperature and develops a coarser grain structure. The applicable size band must be stated when ordering so that the correct minimum is certified.
The quality suffix defines the toughness requirement, and this is the practical difference between grades that share the same yield strength. Here the N variant requires 40 J at minus 20 degC and the NL variant 27 J at minus 50 degC, which suits offshore and cold-climate service. Testing follows EN ISO 148-1 on standard 10 mm by 10 mm V-notch specimens, with tensile testing to EN ISO 6892-1.
The material is supplied normalised or normalised rolled, which gives a fine and uniform grain structure through the section. This condition should be preserved: hot forming above the normalising temperature, or welding with excessive heat input, can coarsen the grain and reduce the certified toughness. Re-normalising after heavy hot working is recommended.
Dimension / Sizes for Carbon Steel S420 Round Bar
Dimension / Size
Value
Unit
Diameter (hot-finished)
8 - 250
mm
Diameter (cold-finished)
Not covered by EN 10025-3
mm
Standard Length (random)
3 - 6
m
Custom / Cut-to-Length
Available on request, typically 0.1 - 12
m
Diameter Tolerance (hot-finished)
Per EN 10060, tolerance class agreed on order
-
Diameter Tolerance (cold-finished)
Not applicable
-
Length Tolerance
Per applicable product standard or as agreed on order
-
Straightness Tolerance
Per applicable product standard or as agreed on order
-
Out-of-Round / Circularity
Controlled by the ordered tolerance class
-
End Condition
Saw cut, sheared, chamfered or centre-drilled as ordered
-
Surface Finish
Hot rolled, hot rolled and descaled, cold drawn, peeled, turned, ground or polished
-
Available Size Range
8 - 250
mm
Cut-to-Length Availability
Yes, subject to minimum order quantity
-
Applicable Dimensional Standard
EN 10060 for hot-rolled round bar
-
Dimensions & Sizes
Explore available diameters, lengths, and dimensional requirements for CS S420 Round Bar
Pricing for Carbon Steel S420 Round Bar
Round Bar Prices are generally quoted per kilograms or meters tonnes and can fluctuate with the global raw material and market prices. The final price will depend on a variety of factors, including the grade size, diameter, length, surface finish, the quantity and whether the bars are cut to length or in standard lengths.
For smaller quantities, we can also quote per metre or per piece basis once the required dimensions have been confirmed. Container-loads or orders that are larger in size are typically priced per tonne, based upon the specifications required and the supply conditions.
Please provide your desired dimensions, grades, length number, and end for a current quote including the lead time applicable and details for certification.
Pricing
Get current Carbon Steel S420 Round Bar pricing based on size, quantity, grade, finish, and delivery requirements.
Why Choose Us
Euro Steel Bars is an international distributor, stockist and exporter of stainless round steel bars that cover carbon, stainless alloy, special grades. We stock a variety of sizes and grades. We guarantee every order with mill test certificates as well as full quality-assurance documentation. Our name speaks to our roots: European-sourced materials that is backed by the certificates and rigor that buyers from Asia as well as the Gulf and Africa are looking for.
Each bar we deliver is accompanied by EN 10204 3.1 mill test certificates as well as complete documentation of quality, so what you receive corresponds to what’s written in the documents. We carry a selection of sizes and grades ready for transport, and cut length upon the request of customers, which results in quicker lead times, whether you’re ordering just a one-off spec or a complete project tonnage.
We operate an actual wholesale business that is that is supported with an internationally-operated supply chain therefore we are able to serve fabricators sourcing one grade the same way in the same way as an EPC contractor who is placing a large order. Our clients include manufacturers, fabricators EPC construction companies, engineers oil and gas projects as well as construction companies. we design our inventory as well as documentation to show what buyers need to bring projects forward.
Our customers trust us across Qatar, Oman, Bahrain, Kuwait, Jordan, Malaysia, Singapore, Thailand, Taiwan, Turkey, Italy and South Africa. If you’re looking to source an Gulf energy project, or a construction project within Southeast Asia, you get the same quality of certified material, the exact documentation, and the exact delivery procedure.
Frequently Asked Questions
What is Carbon Steel S420 Round Bar?
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What sizes, lengths and finishes are available?
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