Designation
| Name |
The value |
| Designation GOST Cyrillic |
20ХГР |
| Designation GOST Latin |
20XGP |
| Transliteration |
20HGR |
| By chemical elements |
20CrMnB |
Description
20KHGR steel is used: for the manufacture of gears, shaft gears, worms, dog clutch, rollers, fingers, bushings, and other improve or case hardening of parts operating under conditions of shock loads.
Note
Structural steel quality chromatorgraphy.
Standards
| Name |
Code |
Standards |
| Sheets and strips |
В23 |
GOST 103-2006 |
| Bars and shapes |
В32 |
GOST 1051-73, GOST 4543-71, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, TU 14-1-2118-77, TU 14-11-245-88, TU 14-136-367-2008 |
| Bars and shapes |
В22 |
GOST 1133-71, GOST 8319.0-75, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006 |
| Blanks. Of the workpiece. Slabs |
В31 |
OST 3-1686-90, TU 14-1-4944-90 |
Chemical composition
| Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
Cu |
V |
B |
Ti |
| GOST 4543-71 |
0.18-0.24 |
≤0.035 |
≤0.035 |
0.7-1 |
0.75-1.05 |
0.17-0.37 |
≤0.3 |
Rest |
≤0.3 |
≤0.05 |
0.001-0.005 |
≤0.06 |
Fe is the basis.
According to GOST 4543-71 the content in high-quality steel is regulated: P≤0,025%; S≤0.025%; Сu≤0.30%; in high-grade steel: P≤0,025%; S≤0.015%; Сu≤0.25%.
Mechanical properties
| Section, mm |
t отпуска, °C |
sT|s0,2, MPa |
σU, MPa |
d5, % |
y, % |
KCU, kJ/m2 |
| Quenching in oil at 880 °C + vacation at 200 °C, cooling in air or in oil |
| ≤15 |
- |
780 |
980 |
9 |
50 |
765 |
| Quenching in oil at 880 °C to + vacation, cooling in oil |
| - |
200 |
1220 |
1490 |
12 |
55 |
765 |
| - |
300 |
1230 |
1420 |
13 |
45 |
549 |
| - |
400 |
1160 |
1250 |
13 |
57 |
736 |
| - |
500 |
850 |
900 |
16 |
66 |
1432 |
| - |
600 |
720 |
790 |
19 |
73 |
1697 |
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 |
a, 10-6 1/°C |
| 0 |
207 |
7800 |
- |
| 300 |
- |
- |
117 |
| 600 |
- |
- |
146 |
A description of the physical symbols
| Name |
Description |
| Е |
The normal elasticity modulus |
| G |
Modulus of elasticity shear torsion |
| r |
Density |
| l |
Coefficient of thermal conductivity |
| R |
UD. the resistivity |
Technological properties
| Name |
The value |
| Склонность к отпускной хрупкости |
malosana |
| The temperature of forging |
Start - 1150 °C, the end - of 800 °C. Sections greater than 75 mm are cooled slowly. |
| Flock-sensitive sensitivity |
not sensitive |
