*** *** Powder Metallurgy Die 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 offers remarkable versatility, providing an exceptional blend of high wear resistance, impressive impact toughness, and superior bend strength. These qualities stem from its fine grain size, minimal carbides, and unparalleled steel cleanliness. PM M4PM M4 extends cutting tool life well beyond that of conventionally-wrought M1.M2,M7and other lower-alloyed high-speed steels. It is particularly effective in cold work tooling applications, significantly outlasting high-carbon, high-chromium die steels like D2 and D3.

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

Common Usage

Ideal for applications such as 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 a 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:
Heat gradually, not exceeding 400°F per hour (222°C per hour), until reaching 1500-1600°F (816-871°C), and then equalize.

Austenizing(High Heat):

Heat rapidly following the preheat.

For Cutting Tools:

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

For maximum toughness, choose the lowest temperature. For maximum hot hardness, opt for the highest temperature.
Quenching:
Utilize pressurized gas, warm oil, or salt for quenching.

For pressurized gas quenching, ensure the furnace maintains a minimum quench pressure of 4 bars. Achieving a quench rate of approximately 400°F (222°C) per minute to below 1000°F (538°C) is essential for the desired properties.

For oil quenching, quench until the material turns black, approximately 900°F (482°C), and then allow it to cool in still air to 150-125°F (66-51°C).

To achieve optimal results with salt processing, maintain temperatures at a precise 1000-1100°F (538-593°C). Allow the material to equalize within the salt bath, then cool it in still air until it reaches a controlled 150-125°F (66-51°C).

Tempering:

Commence tempering immediately following the quenching process for best results.
Temper within the ideal temperature range of 1000-1100°F (538-593°C). Ensure not to temper below 1000°F (538°C). Maintain the chosen temperature for a full 2 hours, followed by air cooling to ambient temperature. Double tempering is essential, and triple tempering is required if austenitized at 2100°F (1149°C) or above.

Annealing:

Conduct annealing post-hot working and prior to any re-hardening processes for optimal results.

Heat at a controlled rate not exceeding 400°F per hour (222°C per hour) until reaching 1550-1600°F (843-871°C). Sustain this temperature for 1 hour per inch (25.4 mm) of thickness, with a minimum of 2 hours. Subsequently, cool slowly with the furnace at a gradual rate not exceeding 50°F per hour (15°C per hour) until 1000°F (538°C) is reached. Continue cooling to ambient temperature either in the furnace or in air for uniform results.