5Cr4Mo2W2VSi Hot Work Tool Steel Properties

5Cr4Mo2W2VSi Tool Steel is a high-performance, medium-carbon tungsten-molybdenum tool steel primarily designed for hot work applications, but also versatile enough for certain cold work tasks. This is a Chinese steel grade.

• Other Designations: It is also known as RM2 or 5Cr4W5Mo2V.
• Type: Hot work tool steel / Matrix steel.

1.  5Cr4Mo2W2VSi Tool Steel Chemical Composition

The typical chemical composition range for 5Cr4Mo2W2VSi Tool Steel is:

• Carbon (C): 0.45 – 0.55%
• Silicon (Si): 0.80 – 1.10%
• Manganese (Mn): ≤ 0.50%
• Phosphorus (P): ≤ 0.030%
• Sulfur (S): ≤ 0.030%
• Chromium (Cr): 3.70 – 4.30%
• Molybdenum (Mo): 1.80 – 2.20%
• Tungsten (W): 1.80 – 2.20%
• Vanadium (V): 1.00 – 1.30%

2. 5Cr4Mo2W2VSi Tool Steel Properties and Advantages

This grade delivers a strong balance of properties crucial for demanding tooling:

• High Hot Strength & Hardness: Maintains structural integrity and hardness at elevated working temperatures.
• Excellent Temperature Resistance: Resists softening during prolonged exposure to heat in service.
• Good Wear Resistance: Offers durability against abrasion and wear, both at ambient and high temperatures, leading to longer tool life.
• Good Toughness & Fatigue Resistance: Provides resistance to chipping and cracking under cyclic stress and impact.
• Thermal Stability: Maintains microstructure and properties reliably at high operating temperatures.
• Good Workability: Can be processed effectively using standard hot and cold working methods.

3.  5Cr4Mo2W2VSi Tool Steel Recommended Heat Treatment

Proper heat treatment is essential to achieve the target properties of 5Cr4Mo2W2VSi Tool Steel.

3.1 Annealing

• Process 1: Heat to 860-880°C, hold for 3-4 hours, furnace cool to below 500°C, then air cool. Hardness: ≤227 HBW.
• Process 2 (Isothermal): Heat to 850-870°C, hold for 2-3 hours, furnace cool to 720-740°C, hold for 3-4 hours, furnace cool to below 500°C, then air cool. Hardness: ≤255 HBW.

3.2 Quenching

• Temperature: 1130-1140°C (Alternatively: 1080°C or 1120°C, depending on specific requirements).
• Medium: Oil cooling (oil at 40-60°C).
• Resulting Hardness: Typically 58-60 HRC (before tempering).

3.3 Tempering

• Process: Double tempering is recommended. Heat to 600-630°C, hold for 2 hours, air cool. Repeat the process.
• Hardness After Tempering: Typically 50-56 HRC (or 57-58 HRC depending on exact parameters).
• Tensile Strength Note: After quenching from 1120°C and tempering at 600°C, Rm is approximately 2055 MPa.

4. 5Cr4Mo2W2VSi Tool Steel Applications

5Cr4Mo2W2VSi is proven in various demanding tool and die applications:

• Hot Extrusion Dies: Especially effective for copper alloys. Often provides significantly longer service life (2-3x, sometimes much more) compared to 3Cr2W8V steel.
• Forging Dies: Suitable for precision forging, flat forging dies, medium/small mechanical press die blocks (operating up to 600-650°C), and gear precision forging dies. Can outperform 5CrNiMo in some hot forging scenarios.
• Punches: Used for hot piercing punches (particularly under lower impact) and bearing ring extrusion punches.
• Edging & Rolling Dies: Demonstrates superior lifespan compared to 4Cr5MoSiV1 and 3Cr2W8V in applications like edging dies and roll forming dies for stainless steel cutlery.
• Dies Under Stable Load: Suitable for dies operating at higher temperatures with relatively stable loads and moderate cooling conditions.
• Cold Working Dies: Its dual-purpose nature allows use in selected cold work tooling.

5. Surface Treatments

To further maximize tool life and performance, standard surface treatments such as nitriding or boronizing can be applied effectively to 5Cr4Mo2W2VSi Tool Steel.