Designation
| Name |
The value |
| Designation GOST Cyrillic |
25Х5М |
| Designation GOST Latin |
25X5M |
| Transliteration |
25H5M |
| By chemical elements |
25Cr5Mo |
Description
25Х5М steel is used: for the manufacture of nitride pump parts, valves, spetskrepezh and other parts which require resistance to oxidation at temperatures up to +600 °C; details of pump-injectors.
Note
Steel martensitic class.
Temperature intense scaling +650 °C.
Standards
| Name |
Code |
Standards |
| Bars and shapes |
В32 |
TU 14-1-749-73, TU 14-1-831-74 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Mo |
| TU 14-1-749-73 |
0.22-0.32 |
≤0.03 |
≤0.03 |
0.3-0.7 |
4-6 |
≤0.5 |
≤0.5 |
Rest |
0.4-0.6 |
Fe is the basis.
According to TU 14-1-749-73, the chemical composition is given for steel grade 25Kh5M. Permissible deviations in the content of elements within ± 0.020%, excluding chrome, sulfur and phosphorus, for which deviations are not allowed.
Mechanical properties
| Section, mm |
sT|s0,2, MPa |
σU, MPa |
d5, % |
y, % |
KCU, kJ/m2 |
| Bars hot rolled on the other 14-1-749-73. The longitudinal samples. Quenching in oil with 865-895 °C + Vacation at 570-630 °C, air cooling |
|
≥686 |
≥780 |
≥8 |
≥50 |
≥490 |
Description mechanical marks
| Name |
Description |
| sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
| σU |
Limit short-term strength |
| d5 |
Elongation after rupture |
| y |
The relative narrowing |
| KCU |
Toughness |
Physical characteristics
| Temperature |
Е, HPa |
r, kg/m3 |
l, W/(m · °C) |
R, Mr. · m |
a, 10-6 1/°C |
С, J/(kg · °C) |
| 20 |
210 |
7750 |
- |
430 |
- |
- |
| 100 |
205 |
7730 |
37 |
- |
113 |
483 |
A description of the physical symbols
| Name |
Description |
| Е |
The normal elasticity modulus |
| r |
Density |
| l |
Coefficient of thermal conductivity |
| R |
UD. the resistivity |
Technological properties
| Name |
The value |
| Weldability |
Difficult weldability. Method of welding: SMAW. Necessary preheating and subsequent heat treatment. |
| Склонность к отпускной хрупкости |
Tend not. |
| The temperature of forging |
Start - 1200 °C, the end - of 800 °C. the cross Sections up to 800 mm is subjected to annealing by recrystallization and single hypothermia. |
| Flock-sensitive sensitivity |
Sensitive. |
| Machinability |
In hot-rolled condition, when blower SB HB 170=390 MPa Kn TV.SPL.=Of 2.7 Kn b.St.=2,0. |
