Special Steel Bar Forged and Rolled

• Customization: Available
• Type: Special Steel Bar
• Standard: AISI, ASTM, DIN, JIS, GB, BS
• Model NO.: round bar
• Technique: Forged
• Shape: Bar
• Surface Treatment: Polished
• 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 SteelD2 Tool Steel is a highly adaptable high-carbon, high-chromium, air-hardening tool steel renowned for its impressive hardness and the presence of significant chromium-rich alloy carbides within its microstructure. These carbides offer exceptional wear resistance against sliding contact with other metals and abrasive substances. While alternative steels may offer enhanced toughness or superior wear resistance, D2 stands out by delivering an optimal balance of hardness, wear resistance, toughness, performance, affordability, and a diverse range of product forms. The remelting process further enhances chemical homogeneity, reduces carbide size, and improves 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, Milled Plate, Black Finish, or customized 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 detailed 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). Then cool it in the furnace at a rate of 20°F (10°C) per hour down to 1200°F (650°C), finally allowing it to cool freely in air.
Stress Relieving
After rough machining, the tool should be uniformly heated to 1200°F (650°C), held for 2 hours, then slowly cooled to 930°F (500°C), and finally allowed to cool freely in air.
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 = the duration at the hardening temperature after the tool is uniformly heated.
Ensure the part is protected against decarburization and oxidation during hardening.
Quenching
Air or pressurized gas to 150-125ºF (66-51ºC). Sizes up to 4 inches (101.6 mm) in thickness will fully harden when air-cooled from 1575ºF (857ºC). Sizes up to 6 inches (152.4 mm) in thickness will fully harden when air-cooled from 1625ºF (885ºC).
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Tempering
Temper immediately after quenching. Hold at the tempering 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 between 300-350°F (149-177°C) to attain a remarkable hardness of 62-64 HRC. For those seeking the perfect harmony between wear resistance and toughness, tempering between 500-550°F (260-288°C) is recommended, resulting in a balanced hardness of 58-60 HRC.
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For exceptional toughness, double tempering is essential. Temper for 2 hours, followed by another 2-hour session at temperatures exceeding 950°F (510°C). This meticulous process will yield a hardness of less than 58 HRC.
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7. D2 Tool Steel Applications
Our D2 tool steel is renowned for its versatile applications, including but not limited to blanking, forming, and trim dies, gages, slitting cutters, wear parts, lamination dies, thread rolling dies, drawing dies, rotary cutting dies, knurls, bending dies, gages, shear blades, burnishing tools, rolls, machine parts, master parts, injection screw and tip components, seaming rolls, extrusion dies, tire shredders, and scrap choppers.

With over a decade of expertise in producing D2 Tool Steel, we are committed to exceeding industry standards. Our D2 Tool Steels are exclusively ESR products, ensuring superior quality. D2 Tool Steel remains our top-selling product. Should you have any inquiries, please do not hesitate to contact us, and we will provide the utmost assistance.