1.4923, X22CrMoV12-1, Z20CDNbV11, St12T
X22CrMoV12-1, designated as EN 1.4923, is a high-strength, creep-resistant martensitic stainless steel engineered for applications requiring exceptional performance at elevated temperatures up to 600°C. Known by various standards such as St12T, AFNOR Z20CDNbV11, ČSN 17134, BS 762, and SEW 555 X21CrhlMoV12-1 (1.4926), this steel is widely used in the production of turbine blades
Table of Contents
What is 1.4923, X22CrMoV12-1, Z20CDNbV11, St12T?
X22CrMoV12-1, designated as EN 1.4923, is a high-strength, creep-resistant martensitic stainless steel engineered for applications requiring exceptional performance at elevated temperatures up to 600°C. Known by various standards such as St12T, AFNOR Z20CDNbV11, ČSN 17134, BS 762, and SEW 555 X 21 CrMoV 12-1, X21CrMoV12-1, 1.4926, this steel is widely used in the production of turbine blades, steam turbine components, and other high-temperature structural parts in power generation, aerospace, and petrochemical industries. Its robust mechanical properties, excellent creep resistance, and good fatigue performance make it a preferred choice for critical applications. This article provides a detailed analysis of X22CrMoV12-1, covering its chemical composition, mechanical properties, heat treatment regimes, physical properties, high-temperature and creep performance, processing, welding characteristics, and equivalent grades.
| Manufacturer | Trade Name | Steel Type | Market Specification | AISI | UNS | Werkstoff | Designation (JIS) | GOST | Advantages |
|---|---|---|---|---|---|---|---|---|---|
| VALBRUNA | VAL2MV | Martensitic | - | - | - | 1.4923 | X22CrMoV12-1 | - | High strength, wear resistance |
| SIEMENS | 1.4923 | Martensitic | 0-2813-4923-00, 1CWW00030, TLV 9248 (03, 02, 06, 08, 07), 203W343, WTLV8248 (21, 41, 06, 07) | - | - | 1.4923 | X22CrMoV12-1 | - | Precision engineering, reliability |
| ANSALDO | 1.4923 | Martensitic | WTLV8248 (21, 41, 06, 07) | - | - | 1.4923 | X22CrMoV12-1 | - | Versatility, industrial use |
| ABB | 1.4923 | Martensitic | 23 90 95, HZLM 00036 | - | - | 1.4923 | X21CrMoNiV12-1 | - | Durability, high-temperature use |
| ALSTOM | 1.4923 | Martensitic | ATD1231001, ATM1230001, 9ANA370206, NB 00141 | - | - | 1.4923 | - | - | Specialized applications |
| NUOVO PIGNONE | 1.4923 | Martensitic | STV M14105, STV M23002, ITN 07763.08/A | - | - | 1.4923 | - | - | High precision, custom solutions |
| MAN | 1.4923 | Martensitic | QSTD-51-216/000 | - | - | 1.4923 | - | - | Toughness, industrial versatility |
| SKODA | 1.4923 | Martensitic | TP 0009 M | - | - | 1.4923 | - | - | Cost-effective, reliable |
Detailed Comparison of Steel Grades
-
Material Composition and Type
- VAL2MV (VALBRUNA): A martensitic steel with the Werkstoff number 1.4923, known for its high strength and wear resistance. The X22CrMoV12-1 designation indicates a composition with chromium, molybdenum, and vanadium, ideal for high-stress applications.
- SIEMENS, ANSALDO, ABB, ALSTOM, NUOVO PIGNONE, MAN, SKODA: All share the same Werkstoff number (1.4923), indicating a similar base composition to VAL2MV. However, their market specifications and designations vary, reflecting differences in processing and intended applications.
-
Werkstoff and Designations
- The Werkstoff number 1.4923 is consistent across all manufacturers, confirming that these steels are equivalents with minor variations. The JIS designation X22CrMoV12-1 (VALBRUNA, SIEMENS, ANSALDO) and X21CrMoNiV12-1 (ABB) suggest slight differences in nickel content or naming conventions.
-
Market Specifications
- SIEMENS provides a wide range of specifications (e.g., TLV 9248 series, WTLV8248 series), indicating its use in precision engineering and diverse industrial applications.
- ABB and ALSTOM focus on specific standards (e.g., HZLM 00036, ATD1231001), likely for high-temperature or specialized uses.
- MAN and SKODA emphasize broader industrial applications with simpler specifications (e.g., QSTD-51-216/000, TP 0009 M).
Applications
X22CrMoV12-1 (1.4923) is primarily used in high-temperature environments where components are subjected to mechanical stress, thermal cycling, and fatigue. Key applications include:
The steel grades covered in this article (EN 1.4923, X22CrMoV12-1, St12T, Z20CDNbV11, ČSN 17134, BS 762, and X21CrMoV12-1) share several important characteristics:
- Turbine Blades: Used in steam and gas turbines for power generation due to its creep resistance and high-temperature strength.
- Compressor Blades: Employed in jet engines and industrial compressors.
- Power Industry Components: Includes turbine discs, shafts, bolts, and screws for thermal engines and power plants.
- Petrochemical Industry: Used in high-pressure vessels and fittings for oil and chemical processing.
- Aerospace: Components requiring elevated strength and fatigue resistance at high temperatures.
- High-temperature strength: These materials maintain excellent mechanical properties at temperatures up to 600°C, with some grades usable up to 650°C
- Good creep resistance: Essential for components subjected to long-term stress at elevated temperatures
- Moderate corrosion resistance: While not as corrosion-resistant as austenitic stainless steels, their chromium content (11-12.5%) provides adequate protection in many environments
- Excellent fatigue resistance: Critical for rotating components like turbine blades
- Hardenability: These steels achieve high strength through quenching and tempering heat treatments
Primary Applications
-
Power generation:
- Steam turbine blades and rotors
- Bolts and fasteners for high-temperature service
- Valve components in power plants
-
Aerospace:
- Engine components
- High-stress fasteners
-
Petrochemical industry:
- Reactor components
- High-temperature piping systems
- Valve bodies and stems
-
General engineering:
- High-strength fasteners
- Pump shafts
- Bearing components
The specific choice of grade depends on the operating temperature, stress levels, and environmental conditions. For example, X22CrMoV12-1 is particularly suited for turbine blades operating in the 500-600°C range , while Z20CDNbV11 may be preferred for certain high-temperature fastener applications.
The steel’s versatility and ability to perform under demanding conditions make it a cornerstone material in industries requiring reliability and durability.
Chemical Composition (%)
The chemical composition of X22CrMoV12-1 (1.4923) and its equivalent grades is tightly controlled to ensure optimal creep resistance, strength, and corrosion resistance. Below is a comparison of the chemical composition based on available data and standards (e.g., EN 10302, EN 10269, and TLV 9367 05 for similar grades like X19CrMoNbVN11-1).
| Element | X22CrMoV12-1, 1.4923 |
X19CrMoNbVN11-1, 1.4913 - TLV 9367 05 |
Z20CDNbV11 - AFNOR |
ČSN 17134 |
Notes |
|---|---|---|---|---|---|
| C | 0.18–0.24% | 0.17–0.23% | 0.18–0.24% | 0.18–0.24% | Carbon enhances strength but is limited to maintain toughness. |
| Si | ≤0.50% | ≤0.50% | ≤0.50% | ≤0.50% | Silicon improves oxidation resistance. |
| Mn | 0.40–0.90% | 0.40–0.90% | 0.40–0.90% | 0.40–0.90% | Manganese improves ductility and toughness. |
| P | ≤0.025% | ≤0.025% | ≤0.025% | ≤0.025% | Low phosphorus ensures better toughness. |
| S | ≤0.015% | ≤0.015% | ≤0.015% | ≤0.015% | Low sulfur minimizes inclusions. |
| Cr | 11.0–12.5% | 10.0–11.5% | 11.0–12.5% | 11.0–12.5% | Chromium provides corrosion and oxidation resistance. |
| Mo | 0.80–1.20% | 0.50–0.80% | 0.80–1.20% | 0.80–1.20% | Molybdenum enhances creep resistance. |
| Ni | 0.30–0.80% | 0.20–0.60% | 0.30–0.80% | 0.30–0.80% | Nickel improves toughness and corrosion resistance. |
| V | 0.25–0.35% | 0.10–0.30% | 0.25–0.35% | 0.25–0.35% | Vanadium contributes to creep strength. |
| Nb | 0.15–0.30% | 0.25–0.55% | 0.15–0.30% | 0.15–0.30% | Niobium improves high-temperature strength. |
| N | ≤0.040% | 0.05–0.10% | ≤0.040% | ≤0.040% | Nitrogen enhances strength in some grades. |
| B | - | ≤0.0015% | - | - | Boron (if present) improves hardenability. |
| Al | - | ≤0.020% (target ≤0.010%) | - | - | Aluminum is minimized to reduce inclusions. |
Sources: TLV 9367 05
Note: The slight variations in composition (e.g., Nb and N content) between X22CrMoV12-1 and X19CrMoNbVN11-1 reflect differences in specific standards or applications, but the grades are closely related and often interchangeable.
Material Properties
The mechanical properties of X22CrMoV12-1 (1.4923) vary depending on the delivery condition (e.g., annealed (+A), heat-treated (+HT), or quenched and tempered (+QT)) and the applicable standard. Below is a summary based on EN 10302, EN 10269, and referenced sources.
Room Temperature Mechanical Properties(+QT1)
| Property | X22CrMoV12-1 (1.4923) | X19CrMoNbVN11-1 (1.4913)(TLV 9367 05) |
|---|---|---|
| 0.2% Proof Strength (MPa) | ≥650 | ≥780 |
| Tensile Strength (MPa) | 800–950 | 900–1050 |
| Elongation A5 (%) | ≥14 | ≥12 (longitudinal), ≥10 (transverse) |
| Reduction of Area (%) | ≥40 | ≥40 (longitudinal), ≥25 (transverse) |
| Impact Energy KV₂ (J) | ≥20 (longitudinal) | ≥20 (longitudinal, avg. of 3, min. 14 J), ≥12 (transverse, min. 10 J) |
| Hardness (HBW) | 240–300 | 265–310 |
High-Temperature Mechanical Properties (550°C, +QT)
| Property | X22CrMoV12-1 (1.4923) | X19CrMoNbVN11-1 (1.4913)(TLV 9367 05) |
|---|---|---|
| 0.2% Proof Strength (MPa) | ≥450 | ≥475 |
| Tensile Strength (MPa) | ≥500 | ≥520 |
| Elongation A5 (%) | ≥15 | ≥16 |
| Reduction of Area (%) | ≥50 | ≥55 |
Transverse Impact Properties at 100°C
- **X19CrMoNbVN11-1 (1.4913)**: Impact energy >20 J (3 samples, TLV 9367 05).
- **FATT (Fracture Appearance Transition Temperature)**: Target <50°C.
High-Temperature and Creep Performance
X22CrMoV12-1 excels in high-temperature environments due to its creep resistance, enhanced by vanadium and niobium additions. Key performance metrics include:
- Creep Rupture Strength: The steel maintains structural integrity under prolonged stress at temperatures up to 600°C. Creep tests (as per TLV 9367 05 for 1.4913) indicate stable performance for extended durations.
- High-Temperature Strength: At 550°C, the steel retains significant strength (≥450 MPa proof strength, ≥500 MPa tensile strength), making it ideal for turbine blades.
- Fatigue Resistance: The material’s martensitic structure and low delta ferrite content (<5%) ensure excellent resistance to cyclic loading.
Physical Properties
The physical properties of X22CrMoV12-1 (1.4923) ensure its suitability for high-temperature applications:
- Density: ~7.7 g/cm³
- Thermal Conductivity: ~25 W/(m·K) at 20°C, decreasing at higher temperatures.
- Thermal Expansion: ~10.5–11.5 × 10⁻⁶/K (20–600°C).
- Specific Heat Capacity: ~460 J/(kg·K) at 20°C.
- Modulus of Elasticity: ~215 GPa at 20°C, reducing to ~180 GPa at 600°C.
Heat Treatment
The heat treatment of X22CrMoV12-1 (1.4923) is critical to achieving its desired properties. Common delivery conditions include:
Annealed (+A)
- Process: Soft annealing at 750–800°C, slow cooling.
- Purpose: Reduces hardness for improved machinability.
- Properties: Lower strength and hardness, suitable for further processing.
Heat-Treated (+HT)
- Process: Normalizing at 1000–1050°C, followed by air cooling.
- Purpose: Refines microstructure and improves toughness.
Quenched and Tempered (+QT)
- Hardening: 1000–1050°C, followed by oil or air quenching.
- Tempering: 650–750°C, minimum 2 hours, air cooling.
- Stress Relieving: As per TLV 0110 (for similar grades like 1.4913, 670–750°C).
- Properties: High strength, creep resistance, and toughness for turbine blades.
Processing Performance
X22CrMoV12-1 is typically supplied as hot-rolled or forged bars, peeled bars, or seamless tubes. Its processing characteristics include:
- Machinability: Good in the annealed condition, but requires robust tools in the +QT state due to high hardness (240–300 HBW).
- Formability: Suitable for forging and rolling, with cast ingots as the starting material (TLV 9367 05).
- Surface Quality: Meets strict cleanliness requirements (e.g., thin series inclusions: Type A, B, C max. 2; Type D max. 2.5; IR(D) ≤10).
- Non-Destructive Testing: Ultrasonic inspection per TWP 1204 ensures internal quality.
Welding Performance
X22CrMoV12-1 has limited weldability due to its high carbon and alloy content, which can lead to cracking in the heat-affected zone (HAZ). Key considerations include:
- Welding Methods: TIG or shielded metal arc welding (SMAW) with matching filler materials.
- Preheating: 200–300°C to reduce thermal stresses.
- Post-Weld Heat Treatment (PWHT): Tempering at 650–700°C to relieve residual stresses and restore toughness.
- Challenges: Risk of martensite formation in the HAZ requires careful control of welding parameters.
For critical applications like turbine blades, welding is often minimized, and components are typically machined from forged or rolled stock.
Equivalent Grades
X22CrMoV12-1 (1.4923) is equivalent or closely related to the following grades:
| Standard | Grade |
|---|---|
| EN | X22CrMoV12-1, 1.4923 |
| AFNOR | Z20CDNbV11 |
| ČSN | 17134 |
| BS | 762 |
| SEW 555 | X21CrMoV12-1, 1.4926 |
| PN-H-84024 | St12T |
| DIN | X20CrMoV12-1 (1.4922, similar) |