This CPM S35VN stainless steel data sheet highlights the edge retention and toughness of this knife steel. CPM S35VN is a tougher version of the popular CPM S30V, due to the addition of niobium. With the addition of .5% niobium, niobium carbides are formed, making CPM S35VN tougher and better able to hold an edge. Machinability and polishibility are also improved.

Chemical Composition

Carbon	1.40%
Chromium	14.00%
Vanadium	3.00%
Molybdenum	2.00%
Niobium	0.50%

Typical Applications

Specialty Cutlery

Wear Components for Food and Chemical Processing

Pelletiziing Blades

Plastic Injection Screws

Corrosion Resistance
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.)

Thermal Treatments
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 S35VN 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

	Austenizing Temp.
Tempering Temp	1900F	1950F	2000F
As Quenched	61	62	63
400F (200C)	58	58	60
600F (315C)	58	59	59
1000F (540C)	57	59	59
Min. Time
at Aust. Temp.	30 min.	30 min.	15 min.
Min. Number
of Tempers	2	2	2

Surface Treatments

Nitriding decreases the corrosion resistance of stainless steels and is generally not recommended for stainless steels.

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 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.

Welding

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)

 

Physical Properties

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)

Grade	Edge Retention	Toughness
	CARTA Test Results	Transverse C-Notch
CPM S35VN	145%	12.0 ft. lbs.
CPM S30V	145%	10.0 ft. lbs.
154 CM	120%	2.5 ft. lbs.
440C	100%	2.5 ft. lbs.

For more information about tool steels and stainless steels suitable for knifemaking see out Knife Steel Introduction article and Data Sheets or our Knife Steel Comparison Chart

CPM® and S35VN® are registered trademarks of Crucible Industries, LLC