Pm M4 Powder Metallurgy High Speed Tool Carbon Steel

• Type: Special Steel Bar
• Standard: AISI, ASTM, DIN, JIS, GB, BS
• Composition: Stainless Steel Scrap
• Technique: Forged
• Shape: Bar
• Surface Treatment: Polished
• Model NO.: powder high speed steel
• 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
• Transport Package: N/M
• Specification: 6-400mm
• Trademark: Smooth
• Origin: China
• HS Code: 7226911000
• Production Capacity: 1000ton/Month

Product Description

PM M4This high-speed tool steel epitomizes versatility, boasting an extraordinary blend of high wear-resistance, superior impact toughness, and remarkable bend strength. These attributes stem from its fine grain size, minuscule carbides, and exceptional cleanliness. PM M4delivers superior cutting tool longevity when compared to traditionally-wrought M1,M2,M7,and other lower-alloyed high-speed steels. PM M4 outperforms high-carbon, high-chromium die steels like D2 and D3 in cold work tooling applications.

Other Known Names:CPM REX M4 steel^®, ASP 2004, S690

Common Usage

Ideal for Broaches, End Mills, Punches, Hobs, Fine Blanking, and Forming Dies.

Physical Properties

Density:

0.286 lb/in³(7806 kg/m³)

Specific Gravity:

7.92

Modulus Of Elasticity:

31 x 10⁶psi (214 GPa)

Machinability:

40-45% of 1% carbon steel

PM M4 High Speed Steel Chemical Composition

						MAXIMUM	TYPICAL
Carbon	Chromium	Tungsten	Molybdenum	Vanadium	Cobalt	Annealed	Tempered
C	Cr	W	Mo	V	Co	Hb	HrC
1.4	4	5.65	5.2	4	-	255	65

 

PM M4 High Speed Steel Heat Treating

ANNEALING	PREHEAT	AUSTENITIZING	QUENCH	TEMPERING
Temp	Temp	Temp	Medium	Temp
°F	°F	°F		°F
1550/1600	1500/1550	2175/2220	Salt/Oil/Atm	1025/1050

 

PM M4 High Speed Steel Thermal Treatments

Preheating:
Gradually heat at a maximum rate of 400°F per hour (222°C per hour) to 1500-1600°F (816-871°C), then equalize.

Austenizing (High Heat):

Heat rapidly from the preheat stage.

For Cutting Tools:

• Soak for 5 to 15 minutes.
• Furnace: 2150-2175°F (1177-1191°C)
• Salt Bath: 2125-2175°F (1163-1191°C)

For Cold Work Tooling:

• Soak for 20 to 45 minutes.
• Furnace: 1875-2125°F (1023-1163°C)
• Salt Bath: 1850-2100°F (1010-1149°C)

To maximize toughness, opt for the lowest temperature. For optimal hot hardness, select the highest temperature.
Quenching:
Utilize pressurized gas, warm oil, or salt.

For pressurized gas, the furnace should maintain a minimum quench pressure of 4 bars. Achieve a quench rate of roughly 400°F (222°C) per minute down to below 1000°F (538°C) to secure the desired properties.

For oil quenching, quench until black (about 900°F or 482°C), then let cool in still air to 150-125°F (66-51°C).

To maintain optimal salt conditions, hold the temperature steady at 1000-1100°F (538-593°C). Let the material equalize in the salt bath, then allow it to cool in still air until it reaches 150-125°F (66-51°C).

Tempering:

Begin tempering immediately after quenching to preserve the material's properties.
The recommended tempering temperature range is 1000-1100°F (538-593°C). Ensure not to temper below 1000°F (538°C). Maintain the material at the tempering temperature for 2 hours, followed by air cooling to ambient temperature. Double tempering is essential, and triple tempering is mandatory when austenitized at 2100°F (1149°C) or higher.

Annealing:

Annealing should be performed post hot-working and prior to re-hardening to ensure material stability.

Heat the material at a controlled rate not exceeding 400°F per hour (222°C per hour) until reaching 1550-1600°F (843-871°C). Maintain this temperature for a minimum of 2 hours, or 1 hour per inch (25.4 mm) of thickness. Gradually cool with the furnace at a rate not exceeding 50°F per hour (15°C per hour) until it reaches 1000°F (538°C). Continue cooling to ambient temperature, either in the furnace or in open air.