AISI D2 / DIN 1.2379 /SKD11 Tool Steel Bar

• Type: Alloy Steel Bar
• Standard: AISI, ASTM, GB, JIS, DIN, BS
• Technique: Forged
• Application: Structural Steel Bar, Tool Steel Bar
• Surface Treatment: Polished
• Alloy: Alloy
• Model NO.: KM-81
• Special Use: Mold Steel, Cold Heading Steel
• Size: 130mm-1000mm (Optional)
• Length: 2m,3m,5.8m, 6m, 8m or as Required.
• Delivery Time: 7-30 Days
• Loading Port: Shanghai
• MOQ: 3 Tons
• Certificate: ISO, BV, SGS, Mill Test Certificate
• Packaging Detail: Standard Sea-Worthy Package
• Surface: Bright, Black
• Price Term: Ex-Work, Fob, CFR, CIF, etc.
• Specifications: Flat Bar, Round Bar, Angle Bar, Square Bar
• Transport Package: Standard Sea-Worthy Package
• Specification: 130mm-1000mm (optional)
• Trademark: Kingmetal
• Origin: China (Mainland)
• Production Capacity: 800tons/Month

Product Description

AISI D2 / DIN 1.2379 /SKD11 tool steel bar

1.Supply Form & Size & Tolerance

Supply Form	Size(mm)	Process	Tolerance
Round	Φ6-Φ100	Cold Drawn	Bright/Black	Best H11
	Φ16-Φ350	Hot Rolled	Black	-0/+1mm
			Peeled/ground	Best H11
	Φ90-Φ1000	Hot Forged	Black	-0/+5mm
			Rough Turned	-0/+3mm
Flat/Square/Block	Thickness :120-800	Hot Forged	Black	-0/+8mm
	Width:120-1500		Rough Machined	-0/+3mm

Remark:Tolerance can be customized as per requests

2.Chemical Composition

Standard	Grade	C	Si	Mn	P	S	Cr	V	Mo
ASTM A681	D2	1.4-1.6	0.1-0.6	0.1-0.6	0.03	0.03	11.0-13.0	0.5-1.1	0.7-1.2
DIN ISO 4957	1.2379	1.45-1.6	0.15-0.6	0.2-0.6	0.03	0.03	11.0-13.0	0.7-1.0	0.7-1.0
JIS G4404	SKD11	1.4-1.6	0.4	0.6	0.03	0.03	11.0-13.0	0.2-0.5	0.8-1.2

3.Physical Property

Temperature		20°C	200°C	400°C
Melting point		1421°C
Density ,kg/m3		7700	7650	7600
Modulus of elasticity,Mpa		210000	200000	180000
Coefficient of thermal expansion	low temperature tempering per °C from 20°C	-	12.3 x 10^-6	-
	high temperature tempering per °C from 20°C	-	11.2 x 10^-6	12 x 10^-6
Thermal conductivity,W/m °C		20	21	23
Specific heat,J/kg °C		460	-	-

4. Mechanical Property

	Metric	Imperial
Hardness, Knoop (converted from Rockwell C hardness)	769	769
Hardness, Rockwell C	62	62
Hardness, Vickers	748	748
Izod impact unnotched	77.0 J	56.8 ft-lb
Poisson's ratio	0.27-0.30	0.27-0.30
Elastic modulus	190-210 GPa	27557-30457 ksi

5.Copressive Strength

Hardness	Compressive yield strength, Rc 0.2
HRC	Mpa	ksi
62	2200	319
60	2150	312
55	1900	276
50	1650	239

6.Forging

Heat the D2 tool steel slowly and uniformly to 700°C then more rapidly to 900-1040°C. Reheat is necessary when temperature is below 900°C.AISI D2 steel  should be cooled as slowly as possible in furnace,and annealing is strongly recommended after forged.

7.Annealing

Annealing must be performed after hot working and before re-hardening. Heat at a rate not exceeding 220°C per hour to 870-900°C, and hold at temperature for 1 hour per inch (25.4mm) of maximum thickness; 2 hours minimum. Then cool slowly with the furnace at a rate not exceeding 20°C per hour to 530°C. Continue cooling to room temperature in the furnace or in air. The resultant hardness should be a maximum of 255 HBW.

8.Sress Relieving 
After rough machining,AISI D2 steel  should be heated throughly to 600-650°C, holding time 2 hours. Cool slowly to 500°C, then freely in air.

9.Hardening

Preheating temperature: 650-750°C.
Austenitizing temperature: 990- 1050°C, but usually 1000-1040°C.

Temperature , °C	Soaking time Min.	Hardness before tempering
990	60	approx. 63 HRC
1010	45	approx. 63 HRC
1030	30	approx. 63 HRC

Quenching Media
• Oil (Only very simple geometries)
• Vacuum (high speed gas)
• Forced air/gas
• Martempering bath or fluidized bed at 180-500°C, then cooling in air.

10.Tempering

Temper immediately after quenching. Hold at temperature for 1 hour per inch (25.4 mm) of thickness, 2 hours minimum, then air cool to ambient temperature. The typical tempering range is 180 to 210ºC.Double tempering is recommended.

Temperature ,°C	150	200	250	300	350	400
Hardness,HRC	62-61	61-60	60-59	57-56	56-55	56-55

11.Application

AISI D2 is used in a wide variety of tool making applications.Use D2 for applications requiring long runs and close tolerances. Use it for tools and dies for blanking, punching, forming, cold-extruding, and other operations requiring high compressive strength and excellent wear resistance.

Typical applications includes :Cutting, punching, stamping tools, shear blades, thread rolling dies, cold extrusion dies, drawing and bending tools, flanging and straightening rolls, fine cutting tools, deep drawing tools, plastic moulds for abrasive polymers