CPM® S45VN
DATA SHEET
Typical Composition
| C | Cr | V | Mo | Nb | N |
|---|---|---|---|---|---|
| 1.48% | 16.00% | 3.00% | 2.00% | 0.50% | 0.15% |
CPM® S45VN is a martensitic stainless steel designed to offer improved corrosion and wear resistance over CPM® S35VN. Its chemistry has been rebalanced so that it forms more chromium carbides, while at the same time leaving more free chromium in the matrix. The use of Niobium and Nitrogen in place of some of the Vanadium and Carbon produces an excellent combination of edge retention, wear resistance, corrosion resistance and toughness properties making this the ideal choice for an EDC knife steel.
The CPM® process produces very homogeneous, high quality steel characterized by superior dimensional stability, grindability and toughness compared to steels produced by conventional melting practices.
Typical Applications include long-wearing specialty cutlery, plastic injection and extrusion feed screws and dies, non-return valve components, pelletizing equipment, and wear components for food and chemical processing. Note: These are some typical applications. Your specific application should not be undertaken without independent study and evaluation for suitability.
CPM® Steel
Conventional Steel
Carbide Type and Volume
| Vanadium | Niobium | Chromium | Total | |
|---|---|---|---|---|
| CPM® S45VN | 3.0% | 0.5% | 11.5% | 15.0% |
| CPM® S35VN | 3.0% | 0.5% | 10.5% | 14.0% |
| CPM® S30V® | 4.0% | 10.5% | 14.5% | |
| 440C | 0% | 12.0% | 12.0% | |
| 154 CM® | 0% | 17.5% | 17.5% | |
| CPM® S90V | 9.0% | 11.0% | 20.0% |
Tool Steel Comparagraph
Physical Properties
Elastic Modules 32 X 10^6 psi (221 GPa)
Density 0.27 lbs./in^3 (7.47 g/cm^3)
Thermal Conductivity
| Temp. | BTU/hr·ft·°F | W/m·°K | cal/cm·s·°C |
|---|---|---|---|
| 200°F (93°C) | 10 | 17.31 | 4.13 × 10−2 |
Coefficient of Thermal Expansion
| °F | °C | in/in/°F | mm/mm/°C |
|---|---|---|---|
| 70 – 400 | (20 – 200) | 6.1 × 10−6 | (11.0 × 10−6) |
| 70 – 600 | (20 – 315) | 6.4 × 10−6 | (11.5 × 10−6) |
Mechanical Properties
Toughness (Transverse Charpy C-notch Testing)
| Grade | Impact Energy |
|---|---|
| CPM® S45VN | 11.0 ft.lbs |
| CPM® S35VN | 12.0 ft.lbs |
| CPM® S30V® | 10.0 ft.lbs |
| 154 CM® | 2.5 ft.lbs |
| 440C | 2.5 ft.lbs |
Although the longitudinal toughness of all four of these grades is about 25-28 ft. lbs., the transverse toughness of the CPM® grades is four or more times that of 440C and 154 CM®. The higher transverse toughness results indicate that CPM® S45VN, CPM® S35VN and CPM® S30V® are much more resistant to chipping and breaking in applications which may encounter side loading. In knifemaking, the higher transverse toughness makes CPM® especially good for bigger blades.
Edge Retention (CATRA Testing Relative to 440C)
| Grade | % |
|---|---|
| CPM® S45VN | 143* |
| CPM® S35VN | 140* |
| CPM® S30V® | 145 |
| 154 CM® | 120 |
| 440C | 100 |
The CATRA (Cutlery & Allied Trades Research Association) test machine performs a standard cutting operation and measures the number of silica impregnated cards which are cut. It is considered a measure of relative wear resistance, reported in this table as compared to a 440C standard.
*Estimate based upon market feedback
Thermal Treatments
Forging: 2100°F (1150°C) Do not forge below 1750°F (950°C).
Annealing: Heat to 1650°F (900°C), hold 2 hours, slow cool no faster than 25°F (15°C) per hour to 1100°F (595°C), then furnace cool or cool in still air to room temperature.
Annealed Hardness: About BHN 255.
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 original tempering temperature, hold 2 hours, then furnace cool or cool in still air.
Straightening: Best done warm 400-800°F (200-425°C).
Hardening
Preheat: Heat to 1550-1600°F (845-870°C) Equalize.
Austenitize: 1900-2000°F (1035-1095°C), hold time at temperature 15-30 minutes.
Quench: Air or positive pressure quench (2 bar minimum) to below 125°F (50°C), or salt or interrupted oil quench to about 1000°F (540°C), then air cool to below 125°F (50°C).
Temper: Double temper at 400-750°F (200-400°C). Hold for 2 hours minimum each time. (See Table) A freezing treatment may be used between the first and second tempers. Freezing treatments help to attain maximum hardenability and must always be followed by at least one temper.
NOTE: For optimum stress relieving, CPM® S45VN may be tempered at 1000-1025°F (540-550°C). Tempering in this range may result in a slight decrease in corrosion resistance.
Size Change: +0.05 to +0.10% when fully martensitic. The presence of retained austenite may reduce the net growth. When tempering at 400-750°F (200-400°C), freezing treatments may be necessary to minimize retained austenite.
Recommended Heat Treatment:
Austenitize 1950°F (1065°C). Quench to below 125°F (50°C). Double temper at 600°F (315°C) 2 hrs. minimum each temper. Cool to hand warm between tempers. A freezing treatment may be added between tempers.
Aim hardness: 59-61 HRC.
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- Hardnesss (HRC)
| Austenitizing Temperature | ||||||
|---|---|---|---|---|---|---|
| 1900°F (1040°C) | 1950°F (1040°C) | 2000°F (1095°C) | ||||
| Tempering Temperature | Oil | Oil & Freeze Liquid N2 | Oil | Oil & Freeze Liquid N2 | Oil | Oil & Freeze Liquid N2 |
| As Quenched | 62.6 | 63.0 | 63.5 | 63.8 | 63.3 | 64.6 |
| 400°F (200°C) | 60.2 | 60.3 | 61.1 | 60.9 | 60.6 | 61.1 |
| 600°F (315°C) | 59.3 | 59.3 | 59.5 | 59.7 | 58.5 | 60.0 |
| 750°F (400°C) | 59.7 | 59.3 | 59.6 | 59.5 | 58.7 | 60.0 |
| 1000°F (540°C) | 59.2 | 59.2 | 60.0 | 59.9 | 61.5 | 62.0 |
| Results may vary with hardening method 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. | ||||||
| Minimum Time at Austenitizing Temperature | 30 min. | 30 min. | 15 min. | |||
| Minimum Number of Tempers | 2 | 2 | 2 | |||
Machinability and Grindability
In the annealed condition, CPM® S45VN is much easier to machine than CPM® S90V and easier to machine than CPM® S30V®. Similar grinding equipment and practices used for high speed steels are recommended. “SG” type alumina wheels or CBN wheels have generally given the best performance with CPM® steels.
Niagara Specialty Metals | 12600 Clarence Center Road, Akron, NY 14001
