Alloy Steel Round Bar Smooth Finish

• 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 SteelD2 Tool Steel is a highly adaptable, high-carbon, high-chromium, air-hardening tool steel. It is renowned for achieving a notable hardness level and contains numerous, substantial chromium-rich alloy carbides within its microstructure. These carbides grant exceptional resistance to wear from sliding contact with other metals and abrasive materials. While there are other steels with enhanced toughness or superior wear resistance, D2 offers a well-balanced blend of wear resistance, toughness, tool performance, value, and various product forms. The remelting process enhances chemical uniformity, refines carbide size, and boosts mechanical and fatigue properties.
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1. Size Range for D2 Tool Steel
D2 Steel Round Bar: Diameter ranging from 80mm to 330mm
D2 Steel Plate: Thickness ranging from 25mm to 400mm; Width spanning 200mm to 800mm
Delivery Condition:
Turned Round Bar, Milling Plate, Black finish as per 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 through to 1560°F (850°C). Then cool in the furnace at 20°F (10°C) per hour down to 1200°F (650°C), followed by free air cooling.
Stress Relieving
After rough machining, the tool should be heated through to 1200°F (650°C) and held for 2 hours. Then, cool slowly to 930°F (500°C) in the furnace, followed by free air cooling.
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 refers to the time at hardening temperature after the tool has been thoroughly heated.
Ensure the part is protected against decarburization and oxidation during hardening.
Quenching
Use air or pressurized gas to cool 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. 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 your Alloy Steel Round Bar Smooth Finish between 300-350°F (149-177°C) to obtain a remarkable hardness of 62-64 HRC. For an optimal equilibrium of wear resistance and toughness, temper between 500-550°F (260-288°C), which will yield a hardness of 58-60 HRC.
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For superior toughness, employ a double tempering process by tempering for 2 hours, then again for another 2 hours, at temperatures above 950°F (510°C). This meticulous procedure will result in a hardness level of less than 58 HRC.
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7. D2 Tool Steel Applications
Widely acclaimed for its versatility, D2 tool steel is ideal for a multitude of applications including blanking, forming, and trim dies, gages, slitting cutters, wear parts, lamination dies, thread rolling dies, drawing dies, rotary cutting dies, knurls, bending dies, shear blades, burnishing tools, rolls, machine parts, master parts, injection screw and tip components, seaming rolls, extrusion dies, tire shredders, scrap choppers, and more.

With over a decade of specialization in producing high-quality D2 Tool Steel, Huangshi Smooth Industry and Trade Co., Ltd is committed to excellence. Our D2 Tool Steels are meticulously crafted to the highest standards through Electro-Slag Remelting (ESR) to ensure superior quality. As our flagship product, D2 Tool Steel stands unrivaled in the market. Should you have any inquiries, please do not hesitate to reach out; we are dedicated to providing exceptional support.