Powder Steel Specification 6-400mm Length

• 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 M4Our high-speed tool steel is a versatile marvel, combining exceptional wear-resistance with remarkable impact toughness and bend strength. This is achieved through the steel's fine grain size, minuscule carbides, and unparalleled cleanliness. PM M4This advanced steel offers significantly enhanced cutting tool life when compared to conventionally wrought M1,M2, M7and other lower-alloyed high-speed steels. It is particularly outstanding in cold work tooling applications, surpassing the performance of high-carbon, high-chromium die steels such as D2 and D3.

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 10⁶ psi (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 at a controlled rate not exceeding 400°F per hour (222°C per hour) to 1500-1600°F (816-871°C), and then equalize.

Austenizing (High Heat):

Heat rapidly from the preheat stage.

For Cutting Tools:

• Soak for a period of 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 a duration of 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. To enhance hot hardness, choose the highest temperature.
Quenching:
Use pressurized gas, warm oil, or salt.

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

For oil quenching, immerse until the steel turns black at approximately 900°F (482°C). Then, allow it to cool in still air until it reaches a temperature of 150-125°F (66-51°C).

For salt bath maintenance, keep the temperature between 1000-1100°F (538-593°C). Allow the steel to equalize in the salt bath, then cool in still air until it reaches a temperature of 150-125°F (66-51°C).

Tempering:

Begin tempering immediately after the quenching process.
The optimal tempering temperature range is 1000-1100°F (538-593°C). Avoid tempering below 1000°F (538°C). Maintain the temperature for 2 hours, then allow the steel to air cool to ambient temperature. Double tempering is necessary. Triple tempering is mandatory when austenitized at 2100°F (1149°C) or higher.

Annealing:

Annealing must be conducted after hot working and prior to re-hardening.

Heat the steel at a rate not exceeding 400°F per hour (222°C per hour) until it reaches 1550-1600°F (843-871°C). Maintain 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 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 air.