CPM S30V is a martensitic stainless steel formulated to provide a good balance of toughness, wear resistance and corrosion resistance. The 4% vanadium in this grade combines with the carbon to form vanadium carbide, providing the wear resistance, while leaving chromium free to provide the corrosion resistance. CPM S30V, manufactured by Crucible Industries, can be hardened as high as RC 60 while maintaining a fair amount of toughness. CPM S30V is a favorite among custom knife makers.
|Wear Components for Food and Chemical Processing|
|Plastic Injection Screws|
|Plastic Extrusion Dies|
Average Pitting Potential measurements from Polarization Curves run in 5% NaCl (Sodium Chloride) Solution at Room Temperature: (Higher voltage pitting potential indicates better corrosion resistance.)
Preheat: Optional preheat stage for unbalanced geometries or complex designs - Heat to 1550-1600°F (845-870°C) Equalize.
Austenize: 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). Accelerated air quenching works well for thin sections, while minimizing warpage.
Tempering: Double temper at 400-750°F (200-400°C). Hold for 2 hours minimum each time. (See Table) A cryogenic treatment may be used between the first and second tempers. Cryogenic treatments help to attain maximum hardenability and must always be followed by at least one temper. NOTE: CPM S30V may be tempered at 1000-1025°F (540-550°C)for optimum stress relieving, . Tempering in this range may result in a slightly lower corrosion resistance.
Cryogenic Treatments: Refrigeration treatments may improve long term dimensional stability by transforming retained austenite. Refrigeration treatments should generally be performed after the first temper, and must be followed by a temper.
Heat Treat Response
|at Aust. Temp.||30 min.||30 min.||15 min.|
Nitriding decreases the corrosion resistance of stainless steels and is generally not recommended for stainless steels.
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
Annealed Material: Heat to 1200/1250F(650/675C), hold two hours, cool in still air.
Hardened Material: Heat to 25F(15C) below original tempering temperature, hold two hours, cool in still air.
Use 440C or 420 stainless steel filler material.
Annealed Material: Preheat 600/800F(320/430C), maintain over 600F(320C) during welding. Reanneal or temper 1200/1400F(650/760C) for 4 hours after welding.
Hardened Material: Preheat to 50F(30C) below original tempering temperature (400F (205C) minimum). Maintain above 400F(205C) during welding. Cool to 150F(65C) after welding. Temper immediately 25F(15C) below original tempering temperature. Minimum 400F(205C)
|Modulus of Elasticity||30psix10(6) (200 GPa)|
|Density||0.278 lb/in3 (7640 kg/M3)|
|Thermal Conductivity||14.0 BTU/hr./ft./F 24.2 W/m/ °K)|
|CARTA Test Results||Transverse C-Notch|
|CPM S30V||145%||10.0 ft. lbs.|
|154 CM||120%||2.5 ft. lbs.|
|440C||100%||2.5 ft. lbs.|