25H2NML
parts for heavy and transport engineering, working in conditions of low temperature and high load conditions; responsible welded-cast structures of large sections of career and draglines.
Classification
Country | Section | Category |
---|---|---|
CIS, Russia, Ukraine | Steels and alloys for castings | Ordinary steel for castings |
Chemical composition
Standard | Fe, % | Si, % | Mn, % | Cr, % | Cu, % | Ni, % | P, % | C, % | S, % | Mo, % |
---|---|---|---|---|---|---|---|---|---|---|
GOST 21357-87 | 95.06–96.68 | 0.2–0.4 | 0.5–0.8 | 1.6–1.9 | < 0.3 | 0.6–0.9 | < 0.02 | 0.22–0.3 | < 0.02 | 0.2–0.3 |
Information on suppliers
Mechanical properties at 20 °C
Rolling | Standard | Size, mm | Tension | Classifiers | $$\sigma _{U}$$, $$MPa$$ | $$\sigma_{P}$$, $$MPa$$ | $$\epsilon_L$$, % | $$\psi$$, % | Treatment |
---|---|---|---|---|---|---|---|---|---|
Castings | GOST 21357-87 | 800 | 700 | 12 | 25 | Hardening in water 860-880 ° C, 580-600 ° C and Holidays |
Heat Treatment Modes
Treatment |
---|
Water hardening 860 - 880 ° C, Release 580 - 600 ° C |
Standards
Standard | Description |
---|---|
GOST 21357-87 |
Description of chemical elements
Element | Units of measurement | Description |
---|---|---|
Fe | % | Iron |
Si | % | Silicon |
Mn | % | Manganese |
Cr | % | Chrome |
Cu | % | Copper |
Ni | % | Nickel |
P | % | Phosphorus |
C | % | Carbon |
S | % | Sulfur |
Mo | % | Molybdenum |
Description of mechanical properties
Parameter | Units of measurement | Description |
---|---|---|
$$\sigma _{U}$$ | $$MPa$$ | Ultimate tensile strength |
$$\sigma_{P}$$ | $$MPa$$ | Proportionality limit |
$$\epsilon_L$$ | % | Elongation at break (longitudinal) |
$$\psi$$ | % | Reduction in cross section on fracture |