20H12VNMF (EP428, 25P2VNMF)
High loaded parts.
highly loaded parts for steam and gas turbines, long operating at temperatures up to 600 ° C .; martensitic steel grade
High loaded parts.
highly loaded parts for steam and gas turbines, long operating at temperatures up to 600 ° C .; martensitic steel grade
Standard | Fe, % | Si, % | Mn, % | Cr, % | Ni, % | V, % | P, % | C, % | S, % | Mo, % | W, % |
---|---|---|---|---|---|---|---|---|---|---|---|
GOST 5632-72 | 82.715–86.98 | < 0.6 | 0.5–0.9 | 10.5–12.5 | 0.5–0.9 | 0.15–0.3 | < 0.03 | 0.17–0.23 | < 0.025 | 0.5–0.7 | 0.7–1.1 |
Temperature, °C | $$E\cdot 10^{9}$$, $$MPa$$ | $$\alpha\cdot 10^{6}$$, $$K^{-1}$$ | $$\varkappa$$, $$\frac{W}{m\cdot K}$$ | $$\rho$$, $$\frac{kg}{m^3}$$ |
---|---|---|---|---|
20 | 212 | 7850 | ||
100 | 207 | 10.6 | 25 | 7830 |
200 | 202 | 10.9 | 25 | 7800 |
300 | 196 | 11.2 | 26 | 7780 |
400 | 190 | 11.4 | 26 | 7760 |
500 | 181 | 11.7 | 27 | 7730 |
600 | 167 | 11.9 | 27 | 7700 |
700 | 12 | 7670 | ||
800 | 12.1 |
Rolling | Standard | Size, mm | Tension | Classifiers | $$\sigma _{U}$$, $$MPa$$ | $$\sigma_{P}$$, $$MPa$$ | $$\epsilon_L$$, % | $$\psi$$, % | $$KCU\cdot 10^{3}$$, $$\frac{J}{m^2}$$ | Treatment |
---|---|---|---|---|---|---|---|---|---|---|
Rod | GOST 5949-75 | 740 | 590 | 15 | 50 | 590 | Hardening of 1010-1060 ° C, the oil, leave 660-670 ° C, air | |||
Rod | GOST 18968-73 | 740 | 590–755 | 15 | 50 | 590 | Normalized and tempered |
Rolling | Standard | Classifiers | Value, HBW |
---|---|---|---|
Rod | GOST 5949-75 | annealing | 229 |
Rod | GOST 18968-73 | normalization, average vacation | 229–269 |
Standard | Description |
---|---|
GOST 5632-72 | |
GOST 5949-75 |
Parameter | Units of measurement | Description |
---|---|---|
$$E\cdot 10^{9}$$ | $$MPa$$ | Elastic modulus |
$$\alpha\cdot 10^{6}$$ | $$K^{-1}$$ | Coefficient of thermal (linear) expansion (range 20°C–T) |
$$\varkappa$$ | $$\frac{W}{m\cdot K}$$ | Coefficient of thermal conductivity (the heat capacity of the material) |
$$\rho$$ | $$\frac{kg}{m^3}$$ | The density of the material |
Parameter | Units of measurement | Description |
---|---|---|
no limits | Welding is performed without heating and without subsequent heat treatment | |
Boundedly welded | Welding is possible with heating up to 100–120 °C and subsequent heat treatment | |
Difficult to weld | For obtaining quality welded joints, additional operations are required: heating up to 200–300 °C for welding, heat treatment after welding — annealing | |
Not applicable for welded structures |