W. NR. 1.2738
Characteristics
Chrome-manganese-nickel-molybdenum steel for hardening in air or in oil with good hardenability and good firmness during the heat. It is well-workable during the heat and well-workable in the soft-annealed state and it has good polishability. The steel has a high ability of the heat treatment into big depths (better than W.Nr.1.2311) with the balanced process of firmness around the whole cross-section. It is appropriate for nitriding and hard-chroming.
Suitability
Mainly heat-treated to the firmness from 950 up to 1100 N/mm2 is used for big molds for plastics injection and big frames of molds.
Chemical composition of steel W.Nr. 1.2738
| Steel grade | Chemical composition in % | Hardness in state | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| soft-annealed | heat-treated | ||||||||||||
| C | Mn | Si | Cr | W | Mo | V | Ni max | Co | P max. | S max. | HB max. | HRC min. | |
| DIN 54NiCrMoV6 | 0,35-0,45 | 1,30-1,60 | 0,20-0,40 | 1,80-2,10 | 0,15-0,25 | 0.90-1,20 | 0,035 | 0,035 | 235 | 51 | |||
| ČSN is not | |||||||||||||
Heat treatment of steel W.Nr. 1.2738
| Way | Temperature [°C] | Procedure | |
|---|---|---|---|
| Forging | 850-1050 | Cool slowly in dry ash or other thermally-insulated material | |
| Soft annealing | 710-740 | Warm few hours (according to the size of object), mostly four hours are enough and cool slowly in the furnace | |
| Annealing to lower tension | 600-650 | Warm 1 to 2 hours and cool slowly in the furnace | |
| Hardening in air or in oil | 840-870 | Cool in oil or in air at 180-220 °C | |
| Tempering | 500-600 | Cool in air, the degree of tempering is set by hardness and toughness of instrument according to the tempering chart | |
Note
Chart of tempering values depending on the hardness:
| °C | 100 | 200 | 300 | 400 | 500 | 600 | 700 |
|---|---|---|---|---|---|---|---|
| HRC | 51 | 50 | 48 | 46 | 42 | 35 | 28 |
| N/mm2 | 1730 | 1670 | 1570 | 1480 | 1330 | 1230 | 920 |
Graph
Product range
Blocks: 1030x1460, 1140x1280, 910x1500
Round bars: D333 - D553
We will deliver any semi-finished products from the above mentioned dimensions. Other dimensions, except for given stock supplies, have to be consulted with us.
