Project Description
AISI 4140 Modified — Advanced Performance Chromium-Molybdenum Alloy Steel
Product Description
SHUNFU METAL offers premium quality AISI 4140 Modified chromium-molybdenum (CrMo) alloy steel bars, featuring enhanced levels of chromium and molybdenum compared to standard 4140 steel. This specialized composition provides increased hardenability, superior through-section properties, and improved performance in demanding applications. Specifically developed for critical oil and gas drilling components, our AISI 4140 Modified steel delivers exceptional strength, toughness, and wear resistance in a wide range of operating environments.
As an API Q1 certified manufacturer with fully calibrated and certified heat treatment furnaces (compliant with AMS 2750), SHUNFU METAL ensures consistent quality through rigorous process controls at every production stage. Each batch undergoes comprehensive testing by CNSA (China National Standards Association) to verify compliance with international standards and customer specifications. Available in multiple strength variants (80ksi, 110ksi, and 125ksi), our AISI 4140 Modified steel provides the optimal combination of properties for downhole drilling tools, including tool joints, shock subs, and other high-stress components where standard 4140 may not provide sufficient performance.
Key Advantages
- Enhanced Hardenability: Higher chromium and molybdenum content provides improved hardenability and more uniform through-section properties compared to standard 4140
- Superior Strength-to-Toughness Ratio: Optimized chemistry and processing deliver excellent combination of strength and impact resistance
- Improved Wear Resistance: Enhanced alloy content contributes to better wear performance in abrasive environments
- Tighter Chemistry Control: Reduced phosphorus and sulfur maximums (0.015% and 0.020% respectively) for superior cleanliness and performance
- Multiple Strength Variants: Available in 80ksi, 110ksi, and 125ksi yield strength versions to suit different application requirements
- Excellent Low-Temperature Toughness: Maintains good impact properties at sub-zero temperatures
- API Q1 Certified Manufacturing: Comprehensive quality assurance system ensures consistent product performance
- AMS 2750 Compliant Heat Treatment: Calibrated furnaces guarantee precise temperature control and property consistency
- 100% Ultrasonic Testing: Complete quality verification with ASTM A388 ultrasonic inspection to API 6A PSL 3&4 standards
- CNSA Verification: Each batch independently tested by China National Standards Association
Chemical Composition
SHUNFU METAL’s AISI 4140 Modified steel features a carefully controlled chemistry with enhanced alloy content:
| Element | Minimum % | Maximum % |
|---|---|---|
| Carbon (C) | 0.40 | 0.43 |
| Silicon (Si) | 0.20 | 0.35 |
| Manganese (Mn) | 0.75 | 1.10 |
| Phosphorus (P) | – | 0.015 |
| Sulfur (S) | – | 0.020 |
| Chromium (Cr) | 0.80 | 1.20 |
| Molybdenum (Mo) | 0.25 | 0.35 |
| Nickel (Ni) | – | 0.25 |
| Aluminum (Al) | 0.015 | 0.030 |
Key Differences from Standard 4140
| Element | Standard 4140 | 4140 Modified | Benefit |
|---|---|---|---|
| Molybdenum (Mo) | 0.15-0.25% | 0.25-0.35% | Increased hardenability, improved high-temperature strength |
| Chromium (Cr) | 0.80-1.10% | 0.80-1.20% | Enhanced hardenability, better wear resistance |
| Carbon (C) | 0.38-0.43% | 0.40-0.43% | Tighter control for more consistent properties |
| Phosphorus (P) | ≤ 0.035% | ≤ 0.015% | Improved toughness and reduced temper embrittlement |
| Sulfur (S) | ≤ 0.040% | ≤ 0.020% | Superior cleanliness and better fatigue properties |
Mechanical Properties
SHUNFU METAL offers AISI 4140 Modified steel in three standard strength variants to meet different application requirements:
80ksi Variant
Ideal for applications requiring optimal toughness and NACE MR0175 compliance:
| Property | Minimum | Maximum |
|---|---|---|
| 0.2% Yield Strength (Proof Stress) | 80 ksi (552 MPa) | – |
| Ultimate Tensile Strength (UTS) | 100 ksi (690 MPa) | – |
| Elongation | 20% | – |
| Reduction of Area | 45% | – |
| Hardness (HRC) | 18 | 22 |
| Hardness (HBW) | 217 | 237 |
Impact Properties (80ksi Variant)
| Test Temperature | Average Value | Minimum Single Value |
|---|---|---|
| Charpy V-Notch @ 23°C (73°F) | 80 J (59 ft-lb) | – |
| Charpy V-Notch @ -32°C (-26°F) | 55 J (41 ft-lb) | 40 J (30 ft-lb) |
| Charpy V-Notch @ -46°C (-51°F) | 42 J (31 ft-lb) | 33 J (24 ft-lb) |
Note: 80ksi variant properties are verified on mid-radial location for 1-10″ diameter bars and at 1″ below surface for 1-12″ diameter bars.
110ksi Variant
Suitable for applications requiring higher strength with good toughness:
| Property | Minimum | Maximum |
|---|---|---|
| 0.2% Yield Strength (Proof Stress) | 110 ksi (758 MPa) | – |
| Ultimate Tensile Strength (UTS) | 135 ksi (931 MPa) | – |
| Elongation | 13% | – |
| Reduction of Area | 40% | – |
| Hardness (HRC) | 30 | 36 |
| Hardness (HBW) | 285 | 341 |
Impact Properties (110ksi Variant)
| Test Temperature | Average Value | Minimum Single Value |
|---|---|---|
| Charpy V-Notch @ 0°C (32°F) | 30 J (22 ft-lb) | 22 J (16 ft-lb) |
| Charpy V-Notch @ -20°C (-4°F) | 27 J (20 ft-lb) | 20 J (15 ft-lb) |
Note: 110ksi variant properties are verified on mid-radial location for 1-10″ diameter bars.
125ksi Variant
Designed for applications requiring maximum strength and hardness:
| Property | Minimum | Maximum |
|---|---|---|
| 0.2% Yield Strength (Proof Stress) | 125 ksi (862 MPa) | – |
| Ultimate Tensile Strength (UTS) | 135 ksi (931 MPa) | – |
| Elongation | 13% | – |
| Reduction of Area | 40% | – |
| Hardness (HRC) | 32 | 38 |
| Hardness (HBW) | 301 | 352 |
Impact Properties (125ksi Variant)
| Test Temperature | Average Value | Minimum Single Value |
|---|---|---|
| Charpy V-Notch @ 0°C (32°F) | 25 J (18 ft-lb) | 20 J (15 ft-lb) |
Note: 125ksi variant properties are verified on mid-radial location for 1-7.5″ diameter bars.
Manufacturing Process
SHUNFU METAL’s AISI 4140 Modified steel is manufactured using advanced processes that ensure premium quality and consistent properties:
Steel Production
- Melting: Electric Arc Furnace (EAF) with precise chemistry control
- Refining: Enhanced Ladle Refining for superior cleanliness and tight compositional control
- Degassing: Extended Vacuum Degassing to achieve low hydrogen content
- Casting: Either bottom-poured wide end up ingots or continuously cast, depending on product requirements
- Reduction Ratio: Minimum 4:1 reduction ratio to ensure optimum grain flow and mechanical properties
Heat Treatment
- Certified Furnaces: All heat treatment performed in AMS 2750 compliant, regularly calibrated furnaces
- Optimized Austenitizing: Controlled heating to optimized austenitizing temperature for enhanced hardenability
- Liquid Quenching: Precision quenching for optimal through-section hardening
- Precision Tempering: Computer-controlled tempering to achieve target mechanical properties
- Stress Relief Options: Available as stress-free or stress-relieved depending on customer requirements
Quality Assurance
- 100% Ultrasonic Testing: Every bar is ultrasonically tested per ASTM A388 with acceptance criteria in accordance with API 6A PSL 3&4
- CNSA Verification: Each batch undergoes independent testing by China National Standards Association
- Microstructural Examination: Verification of grain size (ASTM 5 or finer) and proper microstructure
- Comprehensive Mechanical Testing: Testing for strength, hardness, and impact properties per ASTM standards (A370, E23, E18, E10)
- API Q1 Certified: All manufacturing processes comply with API Q1 quality management system
Applications
AISI 4140 Modified steel from SHUNFU METAL is specifically engineered for demanding applications in oil and gas drilling operations and other critical environments:
Oil and Gas Drilling
- Tool Joints: Critical connection points in drill string assemblies
- Shock Subs: Components that absorb and dampen drilling vibrations
- Drill Collars: Heavy-walled tubular components that provide weight and stiffness
- Stabilizers: Components that maintain drill string alignment
- Crossover Subs: Transition components connecting different thread types
- Top Drive Components: Critical rotating equipment elements
Other Industrial Applications
- High-Stress Gears: Applications requiring superior wear resistance and strength
- Heavy Equipment Components: Critical load-bearing parts in large machinery
- Power Transmission Shafts: Components transmitting high torque
- Aircraft Landing Gear Parts: Components requiring high strength and reliability
- High-Performance Fasteners: Bolts and studs for critical connections
- Automotive Racing Components: Parts subject to extreme stress and fatigue
Specifications and Compliance
SHUNFU METAL’s AISI 4140 Modified steel meets or exceeds the following specifications:
- ASTM A29/A29M: Standard Specification for Steel Bars, Carbon and Alloy, Hot-Wrought
- API 6A: Specification for Wellhead and Tree Equipment
- NACE MR0175/ISO 15156: Materials for use in H₂S-containing environments (80ksi variant)
- AMS 2301: Steel Cleanliness, Aircraft Quality
- AMS 2750: Pyrometry – heat treatment furnace requirements
- API Spec 7: Specification for Drill Stem Elements
Certifications
- API Q1: American Petroleum Institute Quality Management System
- ISO 9001: Quality Management System
- CNSA: China National Standards Association verification
- API 6A PSL 3&4: Product Specification Level for critical service
Product Forms and Sizes
SHUNFU METAL offers AISI 4140 Modified steel in the following forms:
Hot Rolled Bars
- Diameter Range: 1″ to 12″ (25.4mm to 304.8mm)
- Surface Conditions: Black, Peeled, Smooth Turned
- Heat Treatment Conditions:
- 80ksi variant: Hardened and Tempered to 18-22 HRC
- 110ksi variant: Hardened and Tempered to 30-36 HRC
- 125ksi variant: Hardened and Tempered to 32-38 HRC
- Straightness: 1mm in 500mm (1/8″ in 5″)
- Enhanced straightness available upon request
Machining Tolerances
For ‘Machining Quality Bar’ to ASTM A29 Tolerances, the minimum machining allowance is as follows:
| Ordered Surface Condition | Minimum Stock Removal |
|---|---|
| Peeled/Smooth Turned | 1% per side |
| Black | 1.6% per side |
Note: For bars larger than 10.5″ (266.7mm) diameter, the central 20% of the bar will be excluded from ultrasonic testing.
4140 Modified vs. Standard 4140: Comparative Advantages
Understanding the differences between AISI 4140 Modified and standard 4140 helps in selecting the right material for specific applications:
| Performance Characteristic | Standard 4140 | 4140 Modified |
|---|---|---|
| Hardenability | Good | Superior (enhanced Cr and Mo content) |
| Through-Section Properties | Good up to moderate sizes | Excellent in larger sections |
| Wear Resistance | Good | Enhanced |
| Material Cleanliness | Standard (P ≤ 0.035%, S ≤ 0.040%) | Premium (P ≤ 0.015%, S ≤ 0.020%) |
| Low Temperature Toughness | Good | Superior |
| Temper Resistance | Standard | Improved |
| Available Hardness Ranges | Up to 36 HRC | Up to 38 HRC |
| Ultrasonic Quality | Standard | Enhanced due to better cleanliness |
Technical Support and Services
SHUNFU METAL provides comprehensive technical support to help customers maximize the performance of our AISI 4140 Modified steel:
- Application Engineering: Expert assistance in selecting the optimal strength variant for specific applications
- Heat Treatment Consultation: Recommendations for secondary heat treatment when required
- Welding Technical Support: Guidelines for proper welding procedures for 4140 Modified steel
- Failure Analysis: Investigation and root cause analysis of material-related issues
- Custom Testing: Additional mechanical, chemical, or metallurgical testing as required
- Research Collaboration: Technical partnerships for material development and optimization
- Metallurgical Support: Access to experienced metallurgists for technical inquiries
- Quality Documentation: Comprehensive certification packages including detailed processing history
Why Choose SHUNFU METAL for AISI 4140 Modified
Selecting SHUNFU METAL as your supplier for AISI 4140 Modified steel provides numerous advantages:
- API Q1 Certification: Our manufacturing processes are certified to API Q1 quality management system, ensuring consistent quality meeting oil and gas industry requirements
- AMS 2750 Compliant Heat Treatment: Our heat treatment furnaces are regularly surveyed and calibrated to AMS 2750 standards, guaranteeing precise temperature control and consistent properties
- CNSA Verification: Each production batch undergoes independent testing by the China National Standards Association, providing third-party verification of compliance
- QTC Testing: Our Quench, Temper, and Control procedures ensure optimal mechanical properties throughout the material
- Comprehensive Testing: 100% ultrasonic testing to API 6A PSL 3&4 standards, plus mechanical, chemical, and metallurgical analysis
- Technical Expertise: Our team of metallurgists and engineers has extensive experience with alloy steels for critical oil and gas applications
- Supply Chain Reliability: Global sourcing capabilities ensure stable supply and competitive pricing
- Custom Solutions: Ability to tailor products to meet specific customer requirements
- Complete Traceability: Full documentation from melt to final inspection
- Global Service: Worldwide distribution network and technical support
Request Information
Contact SHUNFU METAL today to discuss your AISI 4140 Modified steel requirements. Our technical team is ready to assist you with:
- Detailed technical specifications
- Material selection guidance
- Custom size and property requirements
- Price quotations and delivery schedules
- Quality certification and documentation
- Technical support for your application
We are committed to integrate steel resources in china and serve the global steel market. Our company has more than 15 years of experience in steel researching, production, managing and sales. And our team mostly are based on and worked in national famous steel enterprise before. In the aspect of resources and information, we have established cooperative relationship with nearly hundred enterprises, either state-owned or private owned in China.
What’s more, we have built long, deep and close business relationship with dozens of steel company, Sharing and holding equities with several steel enterprises. Because of the close cooperation with steel companies and our pioneering spirit, which can ensure us stay at the top competition, and ensure our customers get what they really want. We provide preffesional one-stop service to the Contractors of follows project:
- Oil and Gas Pipeline Construction
- Onshore and Offshore
- Boiler Manufacturers
- Oil Refining Equipment
- Petroleum and Chemical Plant Construction
- Fire Protection
- Heating & Air Conditioning
Our ability to purchase materials directly from leading mills at the best possible price will give you the competitive edge. This coupled with a skilled workforce dedicated to embracing the demands of the markets we serve. Just give us a call +86-731-89903933.
