Hot Rolled Annealed JIS SKD12 Air Hardening Tool Steel Flat

JIS SKD12 Cold Work Tool Steel for Making Cutting Tools , Alloy Tool Steel Flats

◆ Equivalence

AISI / SAE	DIN / W.Nr	JIS	GB
A2	1.2363	SKD12	Cr5Mo1V

◆ Chemical Composition (%)

C	Si	Mn	P	S	Cr	Mo	V
0.95 1.05	0.10 0.40	0.40 0.80	≤ 0.030	≤ 0.030	4.80 5.50	0.90 1.20	0.15 0.35

◆ Dimensions

	Hot Rolled	Forged
Thickness (mm)	6-120	60-400
Width (mm)	100-810	60-1500
Length (mm)	2000-5800	2000-5800

◆ Delivery Condition

EAF+(ESR) or EAF+LF+VD+(ESR), Hot rolled or Forged, Annealed, Hardness≤235HB,

Black surface or Machined surface, UT 100% Passed

◆ Characteristics

1. A kind of air hardening tool steel.

2. Good toughness with medium wear resistance and relatively easy to machine.

◆ Applications

Steel Grade JIS SKD12 is usually used for making cutting tools (dies and punches),

blanking and punching tools, thread rolling dies, shear blades, trim dies, forming dies, gauges, stamping dies etc..

◆ Heat Treatment

Annealing

800 to 850°C

Slow controlled cooling in furnace at a rate of 10 to 20°C/hr down to approx. 600°C,

further cooling in air.

Hardness after annealing: max. 235 HB.

Stress relieving

Approx. 650°C

Slow cooling in furnace.

Intended to relieve stresses set up by extensive machining, or in complex shapes.

After through heating, hold in neutral atmosphere for 1 - 2 hours.

Hardening

950 to 980°C

Oil, salt bath (200 to 250°C or 500 to 550°C), air blast, still air.

Tools of intricate shape or with sharp edges should preferably be hardened in air or

salt bath.

Holding time after temperature equalization:15 to 30 minutes.

Obtainable hard ness: 63 - 65 HRC

Tempering

Slow heating to tempering temperature immediately after hardening/time in furnace

1hour for each 20 mm of workpiece thickness, but at least 2 hours/cooling in air.

For average hardness figures to be obtained, please refer to the tempering chart.

For certain cases we recommend to reduce tempering temperature and increase

holding time.

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