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Powder Metal CPM Rex 76 High Speed Tool Steel
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At SteelPro Group, we specialize in providing high-quality tool steels, including the renowned CPM Rex 76. As trusted suppliers, we’re committed to offering only the best materials to meet your toughest demands. Let us guide you through what makes CPM Rex 76 an excellent choice for your next project!
What Is CPM Rex 76 Steel?
CPM Rex 76 is an ultrahigh-speed steel produced via the Crucible Particle Metallurgy (CPM) process. Its high carbon, vanadium, and cobalt content offers wear resistance comparable to T15 and superior red hardness to M42. Capable of reaching HRC 68-70 after heat treatment, it excels in applications requiring exceptional durability and performance at high temperatures. The steel is particularly suitable for high-performance cutting tools and industrial applications.
CPM Rex 76 Steel Products Forms And Supply Range
SteelPro Group’s comprehensive supply range for CPM Rex 76 includes various forms, ensuring versatility for all types of applications. We offer products in multiple dimensions and custom sizes:
Round Bars:
- Diameter: 6 mm to 300 mm (0.24 in to 11.81 in)
Square Bars:
- Side Length: 10 mm to 150 mm (0.39 in to 5.91 in)
Flat Bars:
- Thickness: 5 mm to 100 mm (0.20 in to 3.94 in)
- Width: 20 mm to 250 mm (0.79 in to 9.84 in)
Plate:
- Thickness: 5 mm to 150 mm (0.20 in to 5.91 in)
- Width: 100 mm to 500 mm (3.94 in to 19.69 in)
- Length: 300 mm to 3000 mm (11.81 in to 118.11 in)
CPM Rex 76 Steel Chemical Composition
| Element | Composition (%) |
| Carbon (C) | 1.5 |
| Chromium (Cr) | 3.75 |
| Cobalt (Co) | 8.5 |
| Iron (Fe) | 67.93 |
| Molybdenum (Mo) | 5.25 |
| Sulfur (S) | 0.070 – 0.22 |
| Tungsten (W) | 1 |
| Silicon (Si) | 0.2 |
| Phosphorus (P) | 0.02 |
CPM Rex 76 Steel Physical Properties
| Property | Metric Value | Imperial Value |
| Density | 8.25 g/cc | 0.298 lb/in³ |
| Melting Point | 1,345 °C | 2,443 °F |
| Shrinkage | -0.220 % @ 1190 °C | -0.220 % @ 2170 °F |
| Coefficient of Thermal Expansion (CTE) | 10.66 – 11.74 µm/m·°C | 5.922 – 6.522 µin/in·°F |
| Specific Heat Capacity | 0.43 J/g·K | 0.103 BTU/lb·°F |
CPM Rex 76 Steel Mechanical Properties
| Property | Metric Value | Imperial Value | Note |
| Hardness (HB) | 285 – 311 | 285 – 311 | Annealed |
| Hardness (HRC) | 67 | 67 | Hardening Temper 1200°C; Tempering Temper 525°C |
| 70 | 70 | Hardening Temper 1165°C; Tempering Temper 565°C | |
| Flexural Strength | 2296 MPa | 333000 psi | Hardening Temper 1200°C, Tempering Temper 525°C |
| 4365 MPa | 633100 psi | Hardening Temperr 1165°C, Tempering Temper 565°C | |
| Charpy Impact | 8.00 J | 5.90 ft-lb | Hardening Temper 1200°C; Tempering Temper 525°C |
| 20.0 J | 14.8 ft-lb | Hardening Temper 1165°C; Tempering Temper 565°C | |
| Modulus of Elasticity | 214 GPa | 31000 ksi | – |
CPM Rex 76 Steel Heat Treatment
Annealing
Heat the steel to 870°C (1600°F) and hold for 2 hours.
Then, slow cool at a maximum rate of 15°C per hour (30°F per hour) until the temperature reaches 540°C (1000°F). Once it reaches 540°C, the steel can either be air-cooled or furnace-cooled. After annealing, the hardness will be BHN 285 – 311.
Stress Relieving
Heat the steel to 649°C (1200°F) and hold for 1 hour per 25.44 mm (1 inch) thickness, followed by air cooling. This can be done after forging or machining to reduce internal stresses.
Hardening
Preheating
First, heat to 816-845°C (1500-1550°F) and equalize. Then heat to 1010-1040°C (1850-1900°F).
Austenitizing
Heat rapidly from the preheat temperature to 1177°C (2150°F), ensuring a uniform temperature throughout the steel.
Quenching
- Medium: Pressurized gas, warm oil, or salt.
Pressurized Gas: The furnace should have a minimum quench pressure of 4 bars (58 psi). The quench rate should be approximately 222°C per minute (400°F per minute) to below 538°C (1000°F).
Warm Oil: The quench temperature should be 66-77°C (150-170°F). The quench rate should be approximately 222°C per minute (400°F per minute) to below 538°C (1000°F).
Salt: Quenching in salt should also follow a similar quench rate of 222°C per minute (400°F per minute) until the temperature drops below 538°C (1000°F).
Tempering
Typically done at temperatures ranging from 538°C (1000°F) to 593°C (1100°F) for CPM Rex 76. Hold at the tempering temperature for 1 hour per 15.44 mm (1 inch) of thickness, then air cool. CPM Rex 76 can be heat-treated to achieve a final hardness of HRC 68-70.
CPM Rex 76 Steel Applications
Cutting Tools: High-performance drills, taps, reamers, and end mills used in precision machining.
Forming Tools: Cold work dies, punches, and forming tools for applications requiring high wear resistance.
Molds: Injection molds, die-casting molds, and extrusion dies used in high-stress manufacturing environments.
Cold Heading Tools: Tools for fasteners and other cold-formed parts.
Woodworking Tools: Saw blades, router bits, and planer knives used for woodworking in industrial settings.
Get Custom CPM Rex 76 Tool Steel Solutions
At SteelPro Group, we take pride in supplying CPM Rex 76 and other high-quality tool steels like H13, all provided in an annealed condition for easy machining. Our commitment to quality ensures that you get the perfect material for your needs, with fast lead times and reliable customer support.
If you require further customization or additional processing, don’t hesitate to reach out to us – we’re here to provide tailored solutions that help your business thrive.
