AISI D3 Tool Steel | DIN 1.2080 | GB Cr12 is a kind of cold work tool steel widely used, belonging to Ledeburitic steel with high carbon and high chromium. Quite good hardenability and wearing resistance, and small distortion after quenching. Not good impact toughness, be liable to fracture and form inhomogeneous eutectic carbides.
Dimensions
Round: dia.10-500 mm
Flat: 6-120 x 40-1000 mm
Block: 80-400 x 100-1000 mm
Delivery Condition
EAF+(ESR) or EAF+LF+VD+(ESR), Hot rolled or Forged, Annealed, Black surface or Machined surface, UT SEP1921 Class3 D/d
Equivalence
| AISI/SAE | DIN/W.Nr | JIS | GB | ||||||||
| D3 | 1.2080 | SKD1 | Cr12 |
Chemical Composition(%)
| Steel Grade | C | Sl | Mn | P | S | Cr |
| 1.2080 | 1.90-2.20 | 0.10-0.60 | 0.20-0.60 | ≤0.030 | ≤0.030 | 11.00-13.00 |
| D3 | 2.00-2.35 | 0.10-0.60 | 0.20-0.60 | ≤0.030 | ≤0.030 | 11.00-13.50 |
| Cr12 | 2.00-2.30 | ≤0.40 | ≤0.40 | ≤0.030 | ≤0.030 | 11.50-13.00 |
Applications
1. Common used for making cold work molds of excellent wearing resistance with light shock loads, such as punch heads, cold cutting scissors, drill bushes, gauges, wire drawing sheets, drawing dies, thread rolling dies etc.
2. Making cutting tools which is used for machining material of low hardness.
3. Used as plastic mold with good wearing resistance and long service life.
Forging Technique
| Heat Temperature | Start Forging Temperature | Finish Forging Temperature | Cooling Method | ||||||||
| 1120 - 1140 °C | 1080 - 1100 °C | 880 - 920 °C | Slow Cooling |
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. 250 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
940 to 970°C
Oil, salt bath (220 to 250°C or 500 to 550°C), compressed or still air if thickness does not exceed 25 mm and if hardening temperature is on the upper side of the range. Holding time after temperature equalization: 15 to 30 minutes.
Obtainable hardness: 63 - 65 HRC
Tempering
Slow heating to tempering temperature immediately after hardening/time in furnace
1 hour 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.