Data Sheet - CPM 154
| Typical Composition | ||
| C | Cr | M |
| 1.05 | 14.00 | 4.00 |
CPM 154 is the CPM manufactured version of Crucible’s standard 154 CM. The CPM manufacturing process produces a uniform distribution of the carbides in this grade, giving this CPM 154 easier grinding and polishing, plus better toughness, than conventional 154 CM, while retaining similar heat treat response and wear properties. CPM 154 offers better corrosion resistance, better wear resistance and better hot-hardness than 440C, plus higher toughness. For knifemakers, if offers better edge retention and chipping resistance than 440C.
The CPM process produces very homogenous, high quality steel characterized by superior dimensional stability, grindability, and toughness compared to steels produced by conventional processes.
The typical applications of CPM 154 include cutlery, bearings, and corrosion resistant tooling.
Machinability: Because of the CPM processing, CPM 154 is easier to machine and grind than standard 154 CM. General machining parameters are similar to 154 CM and 440C.
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| Conventional Steel | CPM® Steel |
Mechanical Properties
| Grade | Hardness (HRC) | Wear Resistance | Total Carbide Volume |
| 154 CM | 58.5 | 49 mg | 17.5% |
| 440C | 57.5 | 66 mg, 55mg | 12% |
*Wear resistance measured by the pin abrasion method. Lower number (mg.) is a lower weight loss (in mg) and therefore better wear resistance.
Hot Hardness
| Heat Treatment | Initial HRC | HRC Test at: | Final HRC | ||
| 400°F | 500°F | 600°F | |||
| A | 62 | 59 | 58 | 55 | 60 |
| B | 62 | 55 | 62 | ||
| C | 64 | 57 | 64 | ||
This data sheet is for informational purposes only. Alloy characteristics are subject to change due to chemical composition and/or processing. We do not certify the material’s suitability for specific applications.
Thermal Treatments
Annealing: Heat to 1650°F (900°C), hold 2 hrs., slow cool no faster than 25°F (15°C) per hour to 1200°F (650°C), then furnace cool or cool in still air to room temperature. Crucible 154 CM can be cycle annealed by heating to 1600°F (900°C),hold 2 hours, cool to 1300°F (704°C), hold 4 hours, then air cool.
Annealed Hardness: About BHN 235
Stress Relieving
Annealed Parts: Heat to 1100-1300°F (595-705°C), hold 2 hours, then furnace cool or cool in still air.
Hardened Parts: Heat to 25-50°F (15-30°C) below the original tempering temperature, hold 2 hours, then furnace cool or cool in still air.
Hardening
Preheat: Heat to 1400°F (760°C) Equalize.
Austenitize: 1900-2000°F (1037-1093°C), hold time at temperature 30-60 minutes.
Quench: Oil or positive pressure (4 bar minimum) to below 125°F (50°C) or salt quench to about 1000°F (540°C), then air cool to below 125°F (50°C). Salt bath treatment, if practical, will ensure the maximum attainable toughness for a given hardening treatment.
Temper: Twice at 400-1200°F (204-650°C), 2 hours minimum each time.
Note: As with all martensitic stainless steels, tempering at 800-1100°F (425-600°C) will result in sensitization which causes a minor reduction in both corrosion resistance and toughness. We recommend that this tempering range be avoided.
Aim hardness: HRC 55-62
Note: Properties shown throughout this data sheet are typical values. Normal variations in chemistry, size and heat treat conditions may cause deviations from these values.
| Heat Treat Response HRC Hardness |
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| Austenitizing Temperature | ||||||
| Tempering Temp. | 1900°F (1040°C) |
1950°F (1065°C) |
2000°F (1095°C) |
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| Time at Temp. | 1 hr. | 1 hr. | 30 min. | |||
| Quench (Optional Freeze) | Oil | Oil & Freeze |
Oil | Oil & Freeze |
Oil | Oil & Freeze |
| As Quenched | 62 | 63 | 61 | 63 | 54 | 63 |
| 400°F(204°C) | 59 | 60 | 59 | 62 | 52 | 62 |
| 600°F(315°C) | 56 | 59 | 56 | 60 | 50 | 60 |
| 800°F(427°C) | 56 | 56 | 57 | 60 | 50 | 61 |
| 900°F(482°C) | 56 | 57 | 58 | 61 | 52 | 61 |
| 1000°F(540°C) | 54 | 58 | 60 | 61 | 54 | 63 |
| 1050°F(565°C) | 51 | 52 | 55 | 56 | 52 | 58 |
| Minimum Number of Tempers | 2 | 2 | 2 | |||
| *Results may vary with hardening and section size. Salt or oil quenching will give maximum response. Vacuum or atmosphere cooling may result in up to 1-2 HRC points lower. | ||||||
Recommended Heat Treat Practice
To completely transform any retained austenite, a freezing treatment with dry ice at -100°F(-74°C) is recommended either after the quench or in between the two tempers. The freezing treatment is most effective right out of the quench, however complex parts with sharp corners are more safely frozen between the two tempers. Thin sections can be successfully quenched in forced air and will obtain results to those in the table above.
Surface Treatments
If surface treatments such CVD, PVD, or nitriding are used, ensure that the coating process temperature is below the tempering temperature. Nitriding or tempering at 900°F or higher may reduce the corrosion resistance of CPM 154 or any other stainless steel.