01
ASTM A434 / A434M
Steel bars, alloy, hot-wrought or cold-finished
Standard specification for steel bars, alloy, hot-wrought or cold-finished, quenched and tempered.
Alloy Steel — Industrial Product
Alloy Steel Bar
Low-alloy 4140 steel bar supplied to ASTM A434 / EN 10083, quenched and tempered for machinery and tooling applications.
Indicative priceUSD 850 - 1,150 / MT
Lead time10 - 20 working days
01
Overview
Alloy Steel Bar combines low-alloy 4140 chemistry with chromium and molybdenum additions for reliable high tensile strength, through-hardening response and consistent dimensional control. The quenched and tempered condition delivers proven fatigue resistance and machinability, making the bar suited to machinery shafts, tooling components, stamping dies, cutting tools and high-strength industrial parts. Supplied to ASTM A434 / EN 10083 with mill test certification per EN 10204 3.1, it supports global procurement for mechanical and tooling applications.
Key Characteristics
- 01 High Strength Provides high mechanical strength for demanding structural and industrial applications.
- 02 High Hardness Provides increased surface hardness and resistance to mechanical wear.
- 03 Wear Resistance Provides improved resistance to abrasive and mechanical wear.
- 04 Impact Resistance Offers good resistance to impact loading and sudden mechanical stress.
- 05 Good Toughness Provides good toughness and resistance to brittle fracture.
- 06 Standard Compliance Manufactured and supplied in accordance with the specified material and product standards.
Typical Applications
- Machinery & Equipment Shafts, gears, housings, frames and other components for industrial machinery and OEM equipment.
- Stamping & Machining Metal forming and machining for stamping, deep drawing, CNC machining and forging operations.
- Cutting & Tooling Cutting tools, dies, fixtures, tooling and wear-resistant components.
02
Specifications
Numbers in this section correspond to the applicable product standard, formatted for direct use in enquiry and approval documents.
Product specification
- Material
- Low-alloy steel
- Grade
- 4140 / 1.7225 / 42CrMo4
- UNS designation
- G41400
- Product form
- Bar / rod
- Manufacturing method
- Hot rolled / cold drawn
- Surface / condition
- Mill finish
- Cross-section
- Solid round section (standard); square/hex on request
Supply specifications
- Diameter
- 6 - 300 mm (round); custom sections on request
- Length
- 3 - 12 m; cut-to-length on request
- Tolerance
- According to ASTM A484 / EN 10060
- Surface finish
- Mill finish; turned / polished on request
- Straightness
- <= 2 mm/m
- Marking
- Standard mill marking; customer marking on request
Final supply is confirmed against the project drawing, purchase agreement and the mill test certificate.
Chemical composition
ElementRequirement
C 0.30 - 0.40 %
Si 0.15 - 0.40 %
Mn 0.60 - 0.90 %
P <= 0.035 %
S <= 0.040 %
Cr 0.80 - 1.10 %
Mo 0.15 - 0.25 %
Fe Balance
Reference: applicable standard Alloy Steel.
Mechanical properties
PropertyRequirement
Tensile strength >= 655 MPa
Yield strength (0.2% offset) >= 415 MPa
Elongation in 50 mm >= 18 %
Hardness 197 - 235 HB
Reference: applicable standard Alloy Steel at room temperature.
Physical properties
PropertyTypical Value
Density 7.85 g/cm³
Elastic modulus 205 GPa
Thermal conductivity 42 W/m·K at 100°C
Electrical resistivity 0.22 μΩ·m
Specific heat 475 J/kg·K
Melting range 1,450 - 1,520 °C
Thermal expansion 12.0 x 10⁻⁶ /°C
Reference: Typical material values, Alloy Steel.
Reference framework
Standards & documentation
The applicable product, dimensional and inspection standards should be confirmed together in the purchase specification.
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EN 10083-3
Steels for quenching and tempering - alloy steels
European reference for alloy steels for quenching and tempering, technical delivery conditions.
03
JIS G4104
Chromium steel bars
Japanese reference for chromium steel bars for machine structural use.
04
GB/T 3077
Alloy structural steels
Chinese reference for alloy structural steel hot-rolled bars and billets.
05
DIN 17200
Steels for quenching and tempering
German / European reference for steels for quenching and tempering.
06
EN 10204
Inspection documents
Defines inspection document types such as 3.1 and 3.2 for metallic product delivery.
03
Capability
From custom dimensions and precision sizing to heat treatment, surface finishing and product-specific processing, Wayland coordinates supply solutions tailored to your requirements.
Cutting
Cut-to-length and custom cutting according to order requirements.
Custom Dimensions
Non-standard dimensions, tolerances and dimensional combinations subject to product and mill capability.
Precision Sizing
Precision sizing and dimensional control for tighter tolerance requirements.
Cold Working
Cold drawing, cold sizing and other cold-working processes where required.
Heat Treatment
Heat treatment according to material, specification and applicable standard.
Surface Finishing
Surface treatment and finishing according to product, specification and application requirements.
Machining
Turning, drilling, milling and other machining operations where required.
Forming
Bending, forming and other shape modification according to drawings or order requirements.
Customization
Custom dimensions, lengths, surface conditions, end preparations and inspection requirements can be supplied according to project specifications. Final capability is confirmed per enquiry based on grade, size range and applicable standard.
04
Quality
Inspection and documentation procedures are coordinated to meet the requirements of the applicable product standard and the project specification.
- Dimensional inspection Geometry, dimensions and tolerances against the applicable standard
- Visual and surface inspection Surface condition, marking and overall appearance
Documents
- Inspection Report
- Chemical analysis Per heat, against the applicable standard
- Mechanical testing Tensile, yield, elongation and hardness
- Non-destructive testing UT, eddy-current, hydrostatic or other NDT as applicable
- Positive material identification PMI for alloy verification when required
Documents
- Mill Test Certificate (MTC)
- Heat number traceability Heat number carried through MTC and product marking
- Third-party inspection coordination SGS / BV / TÜV on request
Documents
- Third-Party Inspection Report
- EN 10204 documentation 3.1 MTC standard; 3.2 on request
Documents
- EN 10204 3.1 Mill Test Certificate
- EN 10204 3.2 Inspection Certificate
- Certificate of Origin
05
Selection
A well-prepared specification is the most efficient defence against clarification cycles.
- 01 Select material & grade
Choose the material grade according to service conditions, performance requirements and applicable standards.
- 02 Define size & supply condition
Specify the required dimensions, surface condition, heat-treatment condition and delivery requirements.
- 03 Confirm standard & requirements
State the applicable product standard, dimensional standard and governing project specification.
- 04 Define inspection & documentation
Confirm inspection, testing, certification and documentation requirements before order placement.
Example procurement specification
A complete specification suitable for enquiry, covering product, technical requirements, certification and delivery terms.
- Product
- Alloy Steel Bar
- Grade
- 4140
- Standard
- ASTM A434
- Dimensions
- Ø 25 mm × Length 6000 mm; Annealed
- Condition
- Annealed / Quenched & Tempered; Turned
- Certification
- EN 10204 3.1 Mill Test Certificate
- Quantity
- 20 Metric Tons
- Packaging
- Seaworthy Export Packing
- Incoterm
- CIF Hamburg
06
Logistics
From mill dispatch to destination port, each stage is coordinated with the nominated forwarder and documented against the purchase specification.
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Packaging
Export-suitable packaging with surface and edge protection.
Bundled, wrapped or crated according to product form and transport mode. Outer surface protected with weather-resistant material; ends and edges shielded against transit damage.
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Loading
FCL container for standard sizes; break bulk for oversized cargo.
Container loading via nominated forwarder. LCL and dimensions outside container allowance coordinated against the mill dispatch schedule.
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Documentation
Commercial invoice, packing list and certificate of origin.
Mill documentation travels with the shipment. EN 10204 3.1 / 3.2 certificates and third-party inspection reports provided as per purchase specification.
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Shipment
Sea freight as standard; alternative routes on request.
FCL / LCL container shipment or break bulk for oversized dimensions. Logistics coordinated through the nominated forwarder.
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Delivery
FOB · CFR · CIF · FCA · EXW arrangements available.
Incoterm 2020. Port of loading: Shanghai / Ningbo / Shenzhen. Final destination and terms confirmed per enquiry.
07
FAQ
Most enquiries reduce to a small set of recurring technical questions.
01 What is 4140 alloy steel bar?
4140 alloy bar (42CrMo4 / 1.7225 equivalent) is a chromium-molybdenum through-hardening alloy steel offering high strength, good toughness and good fatigue resistance.
02 What delivery condition is standard?
4140 alloy bar is typically supplied in hot-rolled, hot-rolled annealed, or quenched and tempered condition. Final hardness is confirmed per order.
03 What are typical applications?
4140 bar is widely used for shafts, axles, gears, bolts, studs, tool holders, hydraulic cylinder rods and high-strength machine components.
04 What testing is performed?
Chemical analysis, tensile, hardness, impact and ultrasonic testing per ASTM A434 / EN 10083-3. Additional NDT can be arranged.
05 Can bar be cut to length?
Yes. Saw cut, shear cut and abrasive-wheel cut to length are available. Final tolerance and end finish are confirmed per specification.