AISI 4140 Steel Plate
- Alloy or Not: Alloy
- Thickness: 6 – 150 mm, or as requested
- Width: 900 – 4800 mm, or as requested
- Length: 3000 – 25000 mm, or as requested
- Technique: Hot Rolled, Forged
- Condition: +A/+N/+QT/+HR/+CD, or as requested
- Processing Service: Cutting, Rough/Precision Machining, Polishing, Coating, etc.
- Certification: ISO 9001
- Inspection: SGS, TUV, Factory Inspection
- Origin: Hubei/Henan/Jiangsu, China
- Port: Qingdao, Tianjin, Lianyungang
- MOQ: 5 tons (or as per negotiation)
- Delivery Time: 8-14 Days
- Payment: T/T, L/C
Product Detail
AISI 4140 plate is a low-alloy, high-strength steel, often called chrome-moly or Cr-Mo steel. Its chromium (Cr) and molybdenum (Mo) content provide good strength, hardness, and toughness, making it suitable for demanding mechanical parts. 4140 is commonly used in the machinery manufacturing sector for parts like gears, shafts, bolts, and fittings that require durability and fatigue resistance. Additionally, it offers solid machinability and responds well to heat treatment, making it reliable for automotive parts and industrial equipment applications.
Contact us if you are unfamiliar with this product or have questions unsolved.
Features
AISI 4140 steel plates could bring the following benefits to your project:
- Strong and Durable – Withstands high stress without bending or breaking.
- Resistant to Wear – Lasts longer in tough, abrasive conditions.
- Reliable Toughness – Works well under low temperatures or high pressure.
- Easy to Machine – Suitable for various machining methods, saving time.
- Adjustable Hardness – Can be heat-treated for needed strength and flexibility.
- Fatigue Resistant – Perfect for parts under repeated stress, like machinery.
Applications
Aerospace
Landing gear components, engine parts, structural frames, fasteners, etc.
Automotive
Drive shafts, gears, crankshafts, steering components, etc.
Oil & Gas
Drill collars, pipeline fittings, valve bodies, offshore rig components, etc.
Construction
Steel beams, support structures, heavy-duty machinery, high-strength fasteners, etc.
Tooling
Cutting tools, dies, molds, machine tool parts, etc.
Defense
Armor plates, vehicle components, weapon systems, structural reinforcements, etc.
Product Parameters
| Parameter | Details |
|---|---|
| Standard | AISI, ASTM A29, SAE J404, UNS G41400, AMS 6349, DIN 1.7225, EN 19, GB/T 3077, etc. |
| Grade | 4140, 42CrMo4, 42CrMo, SCM440, 1.7225 |
| Thickness | As requested; 6 – 150 mm; Standard 10/12/15/20/25/30/40/50/60/80/100 mm |
| Width | As requested; 900 – 4800 mm; Standard 1000/1250/1500/2000 mm |
| Length | As requested; 3000 – 25000 mm; Standard 2000/3000/6000 mm |
| Thickness Tolerance | ±1%; or as requested |
| Surface Treatment | Chrome-Plated, Nickel-Plated, Nitrided, Carburized, Black Oxide Coated, Phosphated, etc. |
| Condition of Delivery | +A/+N/+QT/+HR/+CD, or as requested |
| Testing Method | CCA, HB/HRC/HV, NDT, TST, ITT, etc. |
| Application | Drive shafts, gears, crankshafts, steering components, drill collars, pipeline fittings, valve bodies, offshore rig components, steel beams, support structures, heavy-duty machinery, cutting tools, dies, molds, machine tool parts, structural reinforcements, etc. |
| Certification | Approved by ISO 9001 |
| Packaging | Standard seaworthy packing, or as requested |
*Condition of Delivery: A – Annealed, N – Normalized, QT – Quenched & Tempered, HR – Hot Rolled, CD – Cold Drawn
*Testing Method: CCA – Chemical Composition Analysis, HB/HRC/HV – Hardness Testing (Brinell, Rockwell, Vickers), NDT – Non-Destructive Testing, TST – Tensile Strength Testing, ITT – Impact Toughness Testing
Material Specifications
Chemical Composition
| Component | C | Si | Mn | P | S | Cr | Ni | Cu | Mo | More |
|---|---|---|---|---|---|---|---|---|---|---|
| Wt% | 0.38-0.43 | 0.15-0.35 | 0.75-1 | ≤0.035 | ≤0.04 | 0.8-1.1 | ≤0.25 | ≤0.35 | 0.15-0.25 | ** |
*According to ASTM A29/A29M-2012.
*Customer requirement: Si ≤ 0.10%. For certain cold-formed parts, Si ≤ 0.10% should be selected.
*Ni and Cu are residual elements.
**When Pb content is 0.15%-0.35%, add “L” between the second and third digits of the grade, e.g., 41L40. Pb added in the ladle is not heat-analyzed.
Mechanical Properties
| Tensile Strength (σb, MPa) | Yield Strength (σs, MPa) | Elongation After Fracture (δ, %) | Reduction of Area (ψ, %) | Hardness (HB) | Impact Absorption Energy (KV2, J) | |
| +A | +QT | |||||
| 850-1000 | 415-700 | 10-25 | 35-60 | 197-237 | ≥300 | ~35 (varies by treatment) |
*+A – annealed, +QT – quenched and tempered
Why Choose Us
Consistent Quality
We tackle your primary quality concerns with AISI 4140 steel — such as quenching cracks, hardness inconsistency, oxidation scale, and material deformation — through precision heat treatment equipment & advanced quenching media management, automated hardness testing & zonal heating techniques, protective atmospheres & surface treatments, and rigorous deformation control & inspections, to ensure reliable performance, surface quality, and durability.
Precise Dimensions
We guarantee the dimensional accuracy of our S35C plates in accordance with international standards. We can maintain tight tolerances up to ±0.01 mm through precision equipment and ISO 9001-certified processes. Every batch undergoes 100% inspection, with zero deviation complaints in the past 5 years. We ensure smooth project execution without installation delays.
Stable Supply
We have 3 self-operating factories with a combined annual capacity of over 500,000 tons. In the event of any unforeseen circumstances, we can coordinate across factories to ensure stable production and on-time delivery.
Stable & Competitive Pricing
We maintain upstream raw material suppliers with price-lock agreements in place to effectively manage material cost fluctuations. Also, considering that our clients may face pressure from market changes, we will try our best to offer reasonable discounts to both new and existing clients.
Secure Packaging & Shipping
Packaging can be customized according to your requirements. We provide transparent, real-time photos of the packaging and loading process for your verification. You can also choose your trusted freight forwarder for transportation to ensure the entire logistics process is secure and reliable.
About Us
Founded in 1999, SteelPRO Group operates three factories with a combined annual production capacity of over 500,000 tons. We specialize in manufacturing a wide range of steel products, including round steel, profiles, plates, and pipes. Our portfolio encompasses low-alloy structural steel, tool steel, special steel, and more.
With strict adherence to global standards such as GB, ASTM, DIN, EN, and JIS, we ensure high-quality products, including heat-treated, machined, and prestressed steel. Our solutions are trusted by customers in diverse industries, and we proudly export to different countries across Europe, North America, and Asia.
At SteelPRO, we are dedicated to delivering tailored steel solutions and growing alongside our dear clients.
Certification
FAQ
What are your prices?
Our prices are subject to change depending on supply and market conditions. For an accurate and up-to-date quote, please contact our sales team directly.
Can you provide relevant documentation?
Yes, we can provide a wide range of documentation, including Certificates of Analysis/Conformance, Insurance, Certificates of Origin, and any other required export documents.
What is the average lead time?
As per mass production, the lead time is 5-20 days after:
1) we have received your deposit; 2) we have received your final confirmation on your orders.
If our lead time doesn’t meet your deadlines, please contact our sales directly in advance in case of any potential issues. We will try to accommodate your needs in all cases, and we are able to do so in most cases.
Can you provide free samples?
Yes, we can provide free samples for quality evaluation. However, shipping costs are generally covered by your company.
Can I visit your factory?
Of course! You are welcome to visit our factory. Please contact us in advance to arrange a convenient time for your visit, and we will gladly organize a tour and provide any necessary information to ensure a productive visit.
Our Service
SteelPRO Group – manufacturer and solution provider for special steel, offering multi-industry application solutions and customised services, 100% quality free, accompanying customers in their growth!
Our Quality Control
- Roundness
- Tolerance
- Microstructure
- Non-Destructive Testing
- Destructive Testing
- Process Control
Service Integration Processing
- Welding
- Metal Fabrication
- CNC Machining
- Lathe
- Forming
