Steel 20KHNR

Designation

Name The value
Designation GOST Cyrillic 20ХНР
Designation GOST Latin 20XHP
Transliteration 20HNR
By chemical elements 20CrНB

Description

20KHNR steel is used: for the manufacture of gears, shaft gears, worms, dog clutch, rollers, fingers, bushings and other major loaded parts operating under conditions of shock loads.

Note

Structural steel high-quality chrome-Nickel with boron.

Standards

Name Code Standards
Sheets and strips В23 GOST 103-2006
Bars and shapes В22 GOST 1133-71, GOST 8319.0-75, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006
Bars and shapes В32 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
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 0.16-0.23 ≤0.035 ≤0.035 0.6-0.9 0.7-1.1 0.17-0.37 0.8-1.1 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 HB, MPa HRC
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
15-25 - 1370 1420 14 60 1060 - -
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
≤25 - 1370 1420 14 60 1060 418 -
Quenching in oil from 860 °C to + vacation, hladanie in oil
- 200 1220 1520 10 54 481 - 47
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
25-75 - 970 1060 15 60 1060 - -
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
100-150 - 830 1000 16 - 961 286 -
Quenching in oil from 860 °C to + vacation, hladanie in oil
- 300 1200 1400 - - 481 - 46
Normalizing at 930-950 °C, air cooling + tempering in oil with 780-830 °C + vacation at 200 °C, cooling in air or in oil
≤15 - 980 1180 10 50 863 - -
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
25-50 - 1110 1200 - 62 1442 340 -
Quenching in oil from 860 °C to + vacation, hladanie in oil
- 400 1180 1250 11 57 677 - 43
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
50-75 - 970 1060 15 60 1060 302 -
Quenching in oil from 860 °C to + vacation, hladanie in oil
- 500 880 980 14 64 1246 - 34
Normalizing at 930 °C, air cooling + tempering in oil from 840 °C to + vacation at 200 °C, air cooling
75-100 - 920 1000 15 60 1245 302 -
Quenching in oil from 860 °C to + vacation, hladanie in oil
- 600 740 780 16 65 1687 - 28

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
HB Brinell hardness number
HRC Rockwell hardness (indenter diamond spheroconical)

Technological properties

Name The value
Weldability RDS. Recommended heating and subsequent heat treatment.
Склонность к отпускной хрупкости inclined
The temperature of forging Start - 1150 °C, the end - of 800 °C.
Flock-sensitive sensitivity sensitive