1.7709, AFNOR 20CDV5.7, 21CrMoV5.7
1.7709 Heat-Resistant Steel (21CrMoV5-7)
Product Description
FUSHUN METAL’s 1.7709 (21CrMoV5-7) is a premium chromium-molybdenum-vanadium heat-resistant structural steel offering an exceptional combination of high temperature strength, good toughness, and excellent long-term stability at elevated temperatures. With a carefully engineered chemical composition featuring optimized levels of chromium (1.20-1.50%), molybdenum (0.65-0.80%), and vanadium (0.25-0.35%), our 1.7709 delivers outstanding performance in demanding applications requiring mechanical strength at high temperatures up to 550°C. Available in multiple forms including round bars, flat bars, forgings, and custom shapes, this versatile steel is ideal for applications in high-temperature fasteners, turbine components, flanges, rings, and various parts for thermal power plants. The balanced alloy content provides excellent hardenability combined with good toughness and high-temperature stability.
Material Designations and Specifications
1.7709 (21CrMoV5-7) steel conforms to the following standards:
| Material Number | Standards |
|---|---|
| 1.7709 | DIN EN 10269 DIN 17240 AD 2000 W7 |
Chemical Composition
FUSHUN METAL’s 1.7709 (21CrMoV5-7) Steel features the following chemical composition according to standard specifications:
| Element | Min. (%) | Max. (%) |
|---|---|---|
| Carbon (C) | 0.17 | 0.25 |
| Silicon (Si) | 0.15 | 0.35 |
| Manganese (Mn) | 0.40 | 0.80 |
| Phosphorus (P) | – | 0.025 |
| Sulfur (S) | – | 0.030 |
| Chromium (Cr) | 1.20 | 1.50 |
| Nickel (Ni) | – | 0.60 |
| Molybdenum (Mo) | 0.65 | 0.80 |
| Vanadium (V) | 0.25 | 0.35 |
| Aluminum (Al) | – | 0.03 |
Key Element Functions
- Chromium (1.20-1.50%): Enhances hardenability, provides oxidation resistance at elevated temperatures, and improves high-temperature strength.
- Molybdenum (0.65-0.80%): Significantly improves creep resistance, high-temperature strength, and thermal stability for long-term performance at elevated temperatures.
- Vanadium (0.25-0.35%): Forms stable vanadium carbides that refine grain size, enhance high-temperature strength, and improve creep resistance.
- Carbon (0.17-0.25%): Provides optimum hardness and strength after heat treatment while maintaining good toughness.
Properties
1.7709 (21CrMoV5-7) is a chromium-molybdenum-vanadium alloyed heat-resistant structural steel with good toughness. It maintains its mechanical properties during continuous operation at temperatures up to 550°C, making it ideal for high-temperature applications in power generation and industrial equipment.
Delivery Conditions
FUSHUN METAL offers 1.7709 (21CrMoV5-7) in the following conditions:
- Quenched and Tempered (+QT): Optimal combination of strength and toughness
- Quenched, Tempered and Stress Relieved (+QT +SR): Enhanced dimensional stability
- Annealed (+AC): Maximum hardness 229 HBW, improved machinability
Available Product Forms and Dimensions
FUSHUN METAL offers 1.7709 (21CrMoV5-7) Heat-Resistant Steel in a wide range of forms to meet diverse application requirements:
Round Bar Specifications
| Diameter (mm) | Standard Length (mm) | Tolerance | Surface Condition |
|---|---|---|---|
| 10 – 25 | 3000, 6000, Fixed or Random | h9, h10, h11, k12 | Black, Peeled, Turned, Ground, Polished |
| 26 – 100 | 3000, 6000, Fixed or Random | h9, h10, h11, k12 | Black, Peeled, Turned, Ground |
| 102 – 160 | 3000, 6000, Fixed or Random | h9, h10, h11, k12 | Black, Peeled, Turned, Ground |
Flat Bar Specifications
| Thickness (mm) | Width (mm) | Standard Length (mm) | Surface Condition |
|---|---|---|---|
| 5 – 15 | 20 – 100 | 3000, 6000, Fixed or Random | Hot Rolled, Cold Drawn, Ground |
| 16 – 30 | 30 – 150 | 3000, 6000, Fixed or Random | Hot Rolled, Cold Drawn, Ground |
| 32 – 60 | 40 – 200 | 3000, 6000, Fixed or Random | Hot Rolled, Cold Drawn, Ground |
Forged Components
- Flanges and rings
- Turbine shafts
- Custom-forged components
- Near-net shape forgings
- Special shapes according to drawings
Applications
1.7709 (21CrMoV5-7) is designed for components exposed to elevated temperatures up to 550°C:
Application Examples
- Fasteners (bolts, nuts, studs)
- Turbine shafts
- Flanges and rings
- Components for thermal power plants
- High-temperature mechanical parts
- Pressure vessel components
- Steam system parts
- Power generation equipment
Mechanical Properties
1.7709 (21CrMoV5-7) offers excellent mechanical properties according to DIN EN 10269:
Mechanical Properties at Room Temperature (Quenched and Tempered Condition)
| Diameter (mm) | Yield Strength (N/mm²) | Tensile Strength (N/mm²) | Reduction of Area (%) | Elongation (%) | Impact Energy (J) Charpy-V |
|---|---|---|---|---|---|
| ≤ 160 | ≥ 550 | 700 – 850 | ≥ 60 | ≥ 16 | ≥ 63 |
Minimum 0.2% Yield Strength at Elevated Temperatures
| Condition | Diameter (mm) | Temperature (°C) | Yield Strength (N/mm²) |
|---|---|---|---|
| +QT | ≤ 160 | 300 | ≥ 460 |
| +QT | ≤ 160 | 500 | ≥ 350 |
Heat Treatment Guidelines
Recommended heat treatment parameters for 1.7709 (21CrMoV5-7):
| Process | Temperature (°C) | Cooling Medium |
|---|---|---|
| Quenching and Tempering (+QT) | 880 – 950 (Hardening) 680 – 720 (Tempering), min. 2h | Air, Oil, Polymer, Water Air |
Machining Recommendations
To achieve optimal results when machining 1.7709 (21CrMoV5-7) steel, FUSHUN METAL recommends the following parameters:
Annealed Condition (≤ 229 HBW)
| Operation | Tool Material | Cutting Speed | Feed Rate | Coolant |
|---|---|---|---|---|
| Turning | Cemented Carbide P20-P30 | 120-150 m/min | 0.2-0.4 mm/rev | Yes |
| Milling | Cemented Carbide P20-P40 | 100-130 m/min | 0.1-0.3 mm/tooth | Yes |
| Drilling | High Speed Steel | 20-25 m/min | 0.05-0.15 mm/rev | Yes |
| Grinding | Aluminum Oxide Wheel | 25-30 m/sec | – | Yes |
Quenched and Tempered Condition
| Operation | Tool Material | Cutting Speed | Feed Rate | Coolant |
|---|---|---|---|---|
| Turning | Cemented Carbide P10-P20 | 80-100 m/min | 0.15-0.3 mm/rev | Yes |
| Milling | Cemented Carbide P10-P20 | 70-90 m/min | 0.08-0.2 mm/tooth | Yes |
| Drilling | Cemented Carbide | 60-80 m/min | 0.08-0.15 mm/rev | Yes |
| Grinding | Aluminum Oxide Wheel | 25-30 m/sec | – | Yes |
Welding Recommendations
Welding of 1.7709 (21CrMoV5-7) is possible with proper precautions:
- Preheat: 250-350°C recommended
- Interpass Temperature: Maintain 250-350°C
- Post-weld Heat Treatment: Essential – temper at 680-720°C for stress relief
- Filler Materials: Matching composition or low-hydrogen electrodes
- Processes: TIG/GTAW preferred for precision, SMAW possible with proper technique
- Hydrogen Control: Use low hydrogen processes and consumables
Comparative Advantages
Understanding how 1.7709 (21CrMoV5-7) compares to other grades helps in selecting the optimal material for your application:
| Property | 1.7709 (21CrMoV5-7) | 1.7225 (42CrMo4) | 1.4922 (X20CrMoV12-1) |
|---|---|---|---|
| Maximum Operating Temperature | 550°C | 450°C | 600°C |
| High-Temperature Strength | Very Good | Moderate | Excellent |
| Toughness | Good | Excellent | Moderate |
| Oxidation Resistance | Moderate | Limited | Good |
| Cost | Moderate | Low | High |
| Typical Applications | Turbine components, fasteners up to 550°C | General engineering applications | High-temperature steam applications |
Quality Assurance
FUSHUN METAL maintains the highest quality standards for 1.7709 (21CrMoV5-7) Steel:
- Quality Management: ISO 9001, ISO 14001, ISO 50001
- Certifications: Material certificates according to EN 10204 3.1
- Testing: Chemical analysis, mechanical properties testing, ultrasonic testing
- Special Inspections: Available upon request including customer-specific approvals
Why Choose FUSHUN METAL for 1.7709 (21CrMoV5-7) Steel
When you select FUSHUN METAL as your supplier for 1.7709 (21CrMoV5-7) Steel, you partner with a leading manufacturer committed to excellence:
- Heat-Resistant Steel Expertise: Specialized experience in manufacturing premium high-temperature steels
- Advanced Production Facilities: State-of-the-art melting, forging, and processing equipment
- Quality Control: Comprehensive testing protocols ensure consistent performance
- Technical Support: Expert assistance in material selection and application support
- Flexibility: Custom dimensions, tolerances, and surfaces according to customer needs
- Reliability: On-time delivery and consistent product quality
Request Information
Contact FUSHUN METAL today to discuss your 1.7709 (21CrMoV5-7) Steel requirements. Our technical team is ready to assist you with product specifications, technical consultations, and custom processing requirements.
