ČSN 16 326 / 1.6587 / 18CrNiMo7-6
Characteristics
W. Nr. 1.6587 is an alloy steel designed for highly stressed machine components. It is particularly suitable for case-hardened parts, achieving a surface hardness of 62–64 HRC after carburizing while maintaining high core toughness. It is supplied in the soft-annealed condition (+A +TH). The steel has limited weldability.
Suitability
One of the best steels for heavily loaded transmission components, such as crown gears, large drive pinions, gearbox gears, and similar applications. It is also suitable for machine parts requiring both high strength and excellent toughness.
Chemical composition of steel W. Nr. 1.6587
| Steel grade | Chemical composition in % | Hardness in the state | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| soft annealed | heat treated | |||||||||
| C | Si max. | Mn | Cr | Mo | Ni | P max. | S max. | HB max. | HRC max. | |
| W. Nr. 1.6587 | 0,15-0,20 | 0,40 | 0,40-0,60 | 1,50-1,80 | 0,30-0,50 | 1,40-1,70 | 0,035 | 0,035 | 220 | |
Heat treatment of steel W. Nr. 1.6587
| Way | Temperature [°C] | Procedure | |
|---|---|---|---|
| Normalizing annealing | 850-950 | Cooling in air | |
| Soft annealing | 650-700 | Cooling in furnace | |
| Cementation | 880-980 | Directly in oil or warm bath 160-250 °C or cooling in salt bath 580-680 °C or cooling in furnace or in air | |
Hardening to the core Hardening to the surface | 830-870 780-820 |
Cooling in oil or warm bath | |
| Tempering | 150-200 | Min. holding time 1 hour | |
