Cpm S35vn Material Powder Metallurgy Stainless Steel Black Surface Forging Steel Hot Rolled Steel Flat Bar Round Bar

• Type: Special Steel Bar
• Standard: AISI, ASTM, DIN, JIS, GB, BS
• Composition: Stainless Steel Scrap
• Technique: Forged
• Shape: Bar
• Surface Treatment: Polished
• Special Use: High-strength Steel Plate, Wear Resistant Steel, Silicon Steel, Cold Heading Steel, Free Cutting Steel, Mold Steel
• Application: Die Steel Bar
• Length: 2500-5500mm
• Material: HSS
• Usage: Gear Hob
• Customized Support: OEM
• Transport Package: N/M
• Specification: 6-400mm
• Trademark: Smooth
• Origin: China
• HS Code: 7226911000
• Production Capacity: 1000ton/Month

Product Description

Detailed Photos

Product Description

 

CPM S35VN is a martensitic stainless steel designed to offer improved toughness over CPMS30V. It is also easier to machine and polish than CPMS30V. Its chemistry has been rebalanced so that it forms some niobium carbides along with vanadium and chromium carbides. Substituting niobium carbides for some of the vanadium carbides makes CPM S35VN about 15-20% tougher than CPMS30V without any loss of wear resistance. CPMS35VN's improved toughness gives it better resistance to edge chipping. Because both vanadium and niobium carbides are harder and more effective than chromium carbides in providing wear resistance, the CPMstainless blade steels offer improved edge retention over conventional high chromium steels such as 440C and D2. 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.

	Vanadium	Niobium	Chromium	Total
CPM S35VN	3.0%	0.5%	10.5%	14.0%
CPM S30V	4.0%		10.5%	14.5%
440C	0%		12.0%	12.0%
154CM	0%		17.5%	17.5%
CPM S90V	9.0%		11.0%	20.0%

Chemical Composition:

CPM S35VN	Carbon	Chromium	Vanadium	Molybdenum	Niobium
	1.40%	14.00%	3.00%	2.00%	0.50%

      
Physical Properties:
Elastic Modulus     32 X 106psi     (221 GPa)
Density            0.27 lbs./in3     (7.47 g/cm3)
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
70 - 400      (20 - 200)      6.1 X10-6     (11.0 X10-6)
70 - 600      (20 - 315)      6.4 X10-6     (11.5 X10-6)

Mechanical Properties:
Toughness (TransverseCharpy C-notch Testing)

Grade	Impact Energy
CPM S35VN	12.0 ft. Lbs.
CPM S30V	10.0 ft. Lbs.
154CM	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 transversetoughness of the CPMgrades is four or more times that of 440C and 154CM. The higher transverse toughness results indicate that CPMS35VN 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 (CATRATesting Relative to 440C)

Grade	%
CPM S35VN	145*
CPM S30V	145
154CM	120
440C	100

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 S35VN 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: 58-61 HRC.