C
PM S45VN is a martensitic stainless steel designed to offer
enhanced corrosion and wear resistance compared to CPM S35VN. Its rebalanced chemistry promotes the formation of more chromium carbides, while ensuring increased free chromium in the matrix. The incorporation of Niobium and Nitrogen, replacing some Vanadium and Carbon, results in exceptional edge retention, wear resistance, corrosion resistance, and toughness, making it an outstanding choice for EDC knife steel.
The
CPM process generates exceptionally homogeneous, high-quality steel, renowned for its superior dimensional stability, grindability, and toughness, surpassing conventional melting practices.
Typical Applications:
Long-Wearing Specialty Cutlery Plastic Injection and Extrusion Feed Screws and Dies Non-Return Valve Components Pelletizing Equipment Wear Components for Food and Chemical Processing Note: These applications are typical. Ensure suitability through independent study and evaluation before proceeding.
Chemical Composition:
Physical Properties:
Elastic Modulus32 X 10^6 psi
(221 GPa)
Density0.27 lbs./in^3
(7.47 g/cm^3)
Thermal Conductivity
BTU/hr-ft-°F
W/m-°K
cal/cm-s-°C
200°F
93°C
10
17.31
4.13 X 10^-2
Coefficient of Thermal Expansion
°F
°C
in/in/°F
mm/mm/°C
7
0 - 400
(20 - 200)
6.1 X 10^-6
(11.0 X 10^-6)
70 - 600
(20 - 315)
6.4 X 10^-6
(11.5 X 10^-6)
Mechanical Properties:
Toughness(Transverse Charpy C-notch Testing)
While the longitudinal toughness of all four grades is approximately 25-28 ft. lbs., CPM grades exhibit transverse toughness four times or more than that of 440C and 154CM. This superior transverse toughness indicates that CPM S45VN, CPM S35VN, and CPM S30V are far more resistant to chipping and breaking under side-loading conditions. In knifemaking, this makes CPM particularly suitable for larger blades.
Edge Retention(CATRA Testing Relative to 440C)
T
The CATRA (Cutlery & Allied Trades Research Association) test machine performs a standardized cutting operation to measure the number of silica-impregnated cards cut. This test is a benchmark for assessing relative wear resistance, reported in comparison to a 440C standard. *Estimate based upon market feedback
Thermal Treatments:
Forging:
2100°F (1150°C). Refrain from forging below 1750°F (950°C).
Annealing:
Heat to 1650°F (900°C), maintain for 2 hours, then slow cool at a maximum rate of 25°F (15°C) per hour to 1100°F (595°C). Afterward, furnace cool or allow to cool in still air to room temperature.
Annealed Hardness: Approximately BHN 255
Stress Relieving Annealed Parts:
Heat to 1100-1300°F (595-705°C), hold for 2 hours, then cool in a furnace or in still air. For hardened parts, heat to 25-50°F (15-30°C) below the original tempering temperature, hold for 2 hours, then cool in a furnace or in still air.
Straightening:
Optimal results are achieved when straightening warm at 400-800°F (200-425°C). Preheat for hardening: Heat to 1550-1600°F (845-870°C) and equalize.
Austenitize:
1900-2000°F (1035-1095°C), with a hold time at temperature of 15-30 minutes. Quench using air or positive pressure (minimum 2 bar) to below 125°F (50°C), or perform a salt or interrupted oil quench to approximately 1000°F (540°C), then air cool to below 125°F (50°C).
Temper:
Double temper at 400-750°F (200-400°C), holding for a minimum of 2 hours each time. Refer to the table for specifics. A freezing treatment between the first and second tempers can be applied to achieve maximum hardenability and should always be followed by at least one temper.
NOTE: For optimal stress relieving, temper CPM S45VN at 1000-1025°F (540-550°C). Tempering within this range may slightly lower corrosion resistance.
Size Change:
+0.05 to +0.10% when fully martensitic. Retained austenite can reduce net growth. Freezing treatments may be needed when tempering at 400-750°F (200-400°C) to minimize retained austenite.
Recommended Heat Treatment:
Austenitize at 1950°F (1065°C). Quench to below 125°F (50°C). Double temper at 600°F (315°C) for a minimum of 2 hours each temper. Cool to hand warm between tempers. A freezing treatment may be included between tempers.
Target hardness: 59-61 HRC.
Audited Supplier 
){kind=link}