Die Block Steel DB 1
|Properties in hardened and tempered condition||Normalizing Temp. oC||Hardening Temp.oC||Quenching medium||Tempering Temp.oC|
|Tensile strength kgf/mm2||Yield stress Min. kgf/mm2|
|80 - 95||54||810-840||810-840||Oil||550-660|
Protect the steel and heat through to 890°C (1630°F). Then cool in the furnace at 20°C (40°F) per hour to 850°C (1560°f), then at 10°C (20°F) per hour to 700°C (1290°F), then freely in air.
After rough machining the tool should be heated through to 650°C (1200°F), holding time 2 hours. Cool slowly to 500°C (930°F), then freely in air.
- Preheating temperature: 600-850°C (1110-1560°F) .
- Austenitizing temperature: 1020-1050°C (1870-920°F), but usually 1020°C-1030°C (1870-1885°F).
Tensile strength at room temperature
The tensile strength values are to be considered as approximate only. All samples were taken from a bar (in the rolling direction) 25 mm (1″) diameter. Hardened in oil from 1025 ±10°C (1880 ±20°F) and tempered twice to the hardness indicated.
|Hardness||50 HRC||45 HRC|
|Tensile Strength Rm|
|Yield point Rp0,2|
Good results when welding tool steel can be achieved if proper precautions are taken to elevated working temperature, joint preparation, choice of consumables and welding procedure.
For best result after polishing and photo-etching use consumables with the same composition as in the mould.
Choose the tempering temperature according to the hardness required by reference to the tempering graph. Temper minimum twice with intermediate cooling to room temperature.
Lowest tempering temperature 250 °C(480 °F). Holding time at temperature minimum 2 hours
Quenching media and hardenability
• Vacuum, cooling in gas with sufficient over-pressure
• Warm oil, approx. 80°C (175°F)
• Fluidized bed or salt bath at 250-550°C (480¬1020°F) then cool in air blast
• High speed gas/circulating atmosphere
In order to obtain optimum properties, the cooling rate should be as fast as possible while maintaining an acceptable level of distortion. When heating in a vacuum furnace, min. 4-5 bar overpressure is recommended. Note: Temper the tool as soon as its temperature reaches 50-70°C (120-160°F).