Refining
Hardening: quenching and tempering
Quenching consists of the individual process steps of hardening and tempering. During hardening, the material is heated to above the Ac3 line and then quickly quenched. In the case of subsequent tempering, the tempering temperature ultimately determines the elongation and toughness in the component.
The table opposite shows a selection of common heat treatable steels. We’ll be happy to advise you on the choice of materials.
| Reference values for recommended heat treatable steels | |||
|---|---|---|---|
| DIN Nr. | Werkstoff | C-Gehalt | Rm Mpa |
| unalloyed quenched and tempered steels | |||
| 1,1151 | C22E | 0.17 – 0.24 | 500 – 650 |
| 1,1181 | C25E | 0.32 – 0.39 | 630 – 780 |
| 1,1172 | C35EC | 0.32 – 0.39 | 650 – 780 |
| 1,1191 | C45E | 0.42 – 0.50 | 700 – 850 |
| 1,1221 | C60E | 0.57 – 0.65 | 850 – 1000 |
| alloyed heat treatable steels | |||
| 1,5525 | 20MnB4 | 0.18 – 0.23 | 480 – 680 |
| 1,5535 | 23MnB4 | 0.20 – 0.25 | 500 – 700 |
| 1,7182 | 27MnCrB5 | 0.24 – 0.30 | 900 – 1250 |
| 1,7033 | 34Cr4 | 0.38 – 0.45 | 900 – 1100 |
| 1,7035 | 41Cr4 | 0.30 – 0.37 | 1000 – 1200 |
| 1.7220 | 34CrMo4 | 0.38 – 0.45 | 1000 – 1200 |
| 1,7225 | 42CrMo4 | 0.26 – 0.34 | 1100 – 1300 |
| 1.6580 | 30CrNiMo8 | 0.32 – 0.39 | 1250 – 1450 |
| 1,6582 | 34CrNiMo6 | 0.30 – 0.38 | 1200 – 1400 |
| 1,8159 | 51CrV4 | 0.47 – 0.55 | 1100 – 1300 |
Quenching and tempering in a belt furnace under protective gas without edge decarburization
Before tempering: non-tempered ferrite + perlite structure with phaser course from forming
