Cold Work Die Steel Forging Technique

• Type: Special Steel Bar
• Standard: AISI, ASTM, DIN, JIS, GB, BS
• Composition: Stainless Steel Scrap
• Technique: Forged
• Shape: Bar
• Surface Treatment: Polished
• Model NO.: round bar
• Special Use: High-strength Steel Plate, Wear Resistant Steel, Free Cutting Steel, Mold Steel
• Application: Die Steel Bar
• Transport Package: Wooden
• Specification: 6-400mm
• Trademark: Smooth
• Origin: China
• HS Code: 7214100000
• Production Capacity: 5000

Product Description

1.2379/D2/SKD11

Brief Description
D2 Tool Steel is a versatile high-carbon, high-chromium, air-hardening tool steel characterized by its high attainable hardness and abundant chromium-rich alloy carbides. These carbides endow the steel with exceptional wear resistance against sliding contact with metals and abrasive materials. While alternatives may offer enhanced toughness or superior wear resistance, D2 strikes a remarkable balance between wear resistance, toughness, tool performance, cost-effectiveness, and diverse product forms. The remelting process enhances chemical homogeneity, refines carbide size, and improves both mechanical and fatigue properties.
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1. Size Range for D2 Tool Steel
D2 Steel Round Bar: diameter 80mm~330mm
D2 Steel Plate: thickness 25mm~400mm x width 200mm~800mm
Delivery Condition:
Turned Round Bar, Milling Plate, Black, tailored to customer requirements.
Spheroidizing Annealing, ESR material.
2. D2 Tool Steel Equivalent Grades

Country	USA	German		Japan	China
Standard	ASTM A681	W-nr.	DIN	JISG4404	GB/T1299-2000
Grades	D2	1.2379	X155CrVMo121	SKD11	Cr12Mo1V1

3. D2 Tool Steel Chemical Composition

Grades	C%	Si%	Mn%	P%	S%	Cr%	Mo%	V%
D2	1.40~1.60	0.30~0.50	0.30~0.50	≤0.03	≤0.03	11.0~13. 0	0.70~1.20	0.80~1.10
1.2379/X155CrVMo121	1.50~1.60	0.10~0.40	0.15~0.45	≤0.03	≤0.03	11.0~12.0	0.60~0.80	0.90~1.10
SKD11	1.40~1.60	≤0.40	≤0.60	≤0.030	≤0.030	11.0~13. 0	0.80~1.20	0.20~0.50

4. D2 Tool Steel Physical Properties
The physical properties of D2 Tool Steel are outlined in the tables below. The elastic modulus is 207,000 MPa, and the specific heat at constant pressure (Cp) is 461 J/(kg·K).
Critical temperature of D2 Tool Steel

Critical point	Ac1	Acm	Arcm	Ar1	Ms
Temp.(approximation)	1490°F (810°C)	1607°F (875°C)	1382°F (750°C)	1283°F (695°C)	374°F (190°C)

Coefficient of linear thermal expansion

Temperature	68~212°F (20~100°C)	68~392°F (20~200°C)	68~572°F (20~300°C)	68~752°F (20~400°C)
Coefficient	10.5 x10^-6	11.5 x10^-6	11.9 x10^-6	12.2 x10^-6

5. Forging of D2 Tool Steel

Items	Heating temperature	Starting forging temperature	Final forging temperature	Cooling
Ingot	2048~2120°F (1120~1160°C)	1922~1994°F (1050~1090°C)	≥1562°F(850°C)	Hot charging annealing
billet	2048~2084°F (1120~1140°C)	1922~1958°F (1050~1070°C)	≥1562°F(850°C)	Hot charging annealing,cooling in hole or dust

6. Heat Treatment
Soft Annealing
Protect the steel and heat it uniformly to 1560°F (850°C). Cool in the furnace at 20°F (10°C) per hour down to 1200°F (650°C), then cool freely in air.
Stress Relieving
After rough machining, heat the tool uniformly to 1200°F (650°C) and hold for 2 hours. Cool slowly to 930°F (500°C), then allow to air cool freely.
Hardening
Preheating temperature: 1110-1290°F (650-750°C). Austenitizing temperature: 1810-1920°F (990-1050°C), typically 1830-1905°F (1000-1040°C).

Temperature		Soaking time (min)	Hardness before tempering
°F	°C
1815	990	60	approx. 63 HRC
1850	1010	45	approx. 64 HRC
1885	1030	30	approx. 65 HRC

* Soaking time = duration maintained at hardening temperature after the tool is thoroughly heated through.
Protect the part from decarburization and oxidation during the hardening process.
Quenching
Air or pressurized gas to 150-125ºF (66-51ºC). Sizes up to 4 inches (101.6 mm) in thickness will through-harden when air-cooled from 1575ºF (857ºC). Sizes up to 6 inches (152.4 mm) in thickness will through-harden when air-cooled from 1625ºF (885ºC).
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Tempering
Temper immediately after quenching. Maintain the temperature for 1 hour per inch (25.4 mm) of thickness, with a minimum of 2 hours, then air cool to ambient temperature. The typical tempering range is 350 to 400ºF (177 to 204ºC).
To achieve unparalleled wear resistance, temper your steel between 300-350°F (149-177°C) to attain a superior hardness range of 62-64 HRC. Should you seek the perfect equilibrium between wear resistance and toughness, a tempering range of 500-550°F (260-288°C) will yield an impressive hardness of 58-60 HRC.
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For those requiring maximum toughness, a double tempering process is recommended: 2 hours followed by an additional 2 hours at temperatures exceeding 950°F (510°C). This meticulous technique will result in a hardness of less than 58 HRC, ensuring optimal durability.
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7.D2 Tool Steel Applications
D2 tool steel is renowned for a multitude of applications including blanking, forming, and trim dies, gages, slitting cutters, wear components, lamination dies, thread rolling dies, drawing dies, rotary cutting dies, knurls, bending dies, gages, shear blades, burnishing tools, machine parts, master parts, injection screw and tip components, seaming rolls, extrusion dies, tire shredders, and scrap choppers, among many others.

With over a decade of expertise, Huangshi Smooth Industry and Trade Co., Ltd proudly specializes in producing D2 Tool Steel. Our commitment to superior quality is evidenced by our exclusive use of ESR (Electro Slag Remelting) for all D2 products. As our flagship product, D2 Tool Steel has consistently been our bestseller. Should you have any inquiries, please do not hesitate to contact us; we are dedicated to providing the utmost assistance!