Steel 20G (20Г1)

Designation

Name The value
Designation GOST Cyrillic 20Г
Designation GOST Latin 20G
Transliteration 20G
By chemical elements 20Mn
Name The value
Designation GOST Cyrillic 20Г1
Designation GOST Latin 20G1
Transliteration 20G1
By chemical elements 20Mn1

Description

Steel 20G used: for the manufacture after the improvement of the rivets for critical applications; after cementation, or cyanidation — piston pins, friction discs, finger springs, Cam rollers, bolts, nuts, gears, worms, and other parts with high hardness and wear resistance of the surface; without the heat treatment as welded sub frames, shoes, scarves; cold-drawn tubes for the manufacture of bushings of the track link and piston pins for engines of tractors; the bars used for the manufacture of car parts.

Note

Steel structural quality manganese.

Standards

Name Code Standards
Bars and shapes В32 GOST 1051-73, GOST 4543-71, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 10702-78, GOST 14955-77, GOST 1050-2013, TU 14-1-2118-77, TU 14-11-245-88, TU 14-1-1271-75, TU 14-1-5228-93, TU 14-136-367-2008
Bars and shapes В22 GOST 1133-71, GOST 8278-83, GOST 8281-80, GOST 8282-83, GOST 8283-93, GOST 8319.0-75, GOST 9234-74, GOST 11474-76, GOST 2590-2006, GOST 2591-2006, TU 14-2-341-78
Sheets and strips В33 GOST 1577-93, TU 14-1-522-93, TU 14-1-1832-76, TU 14-1-522-73
Sheets and strips В23 GOST 82-70, GOST 19903-74, GOST 103-2006, GOST 19903-90
Blanks. Of the workpiece. Slabs В31 OST 3-1686-90, TU 14-1-4944-90
Steel pipes and fittings to them В62 TU 14-3-316-74, TU 14-3-575-90

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Ti Mo W
GOST 4543-71 0.17-0.24 ≤0.035 ≤0.035 0.7-1 ≤0.3 0.17-0.37 ≤0.3 Rest ≤0.3 ≤0.05 ≤0.03 ≤0.15 ≤0.2
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, % d d10 y, % HB, MPa HRC
Hot-rolled steel and hot rolled with special surface finish
- - - - - - - - ≤179 -
Steel calibrated and calibrated with special surface finish
- - - - - - - - ≤187 -
The strip in the delivery condition (without heat treatment in the etched condition) on the other 14-1-522-93
- - ≥275 ≥450 ≥24 - - - - -
Normalizing at 880°C, air.
≤25 - ≥275 ≥450 ≥24 - - ≥50 - -
Quenching in water from 890 °C to + leave 450 °C, oil
20 - ≥390 ≥450 - ≥8 - ≥67 - -
Quenching in water from 890 °C to + vacation 400-600 °C, oil
- 400 ≥920 ≥980 - - ≥6 ≥67 - -
Normalization at 900 °C, air + vacation at 610 °C, air cooling
≤650 - ≥235 ≥430 ≥24 - - - 126-163 -
Quenching in water from 890 °C to + leave 450 °C, oil
40 - ≥300 ≥360 - ≥12 - ≥74 - -
Quenching in water from 890 °C to + vacation 400-600 °C, oil
- 500 ≥700 ≥780 - - ≥12 ≥74 - -
Quenching in water from 890 °C to + leave 450 °C, oil
60 - ≥210 ≥270 - ≥16 - ≥78 - -
Quenching in water from 890 °C to + vacation 400-600 °C, oil
- 600 ≥540 ≥640 - - ≥15 ≥79 - -
Cementation at 900-920 °C, air cooling + tempering in oil 780-800 °C + vacation 180-200 °C, air
≤25 - 325-370 540-590 ≥16 - - ≥40 146-163 57-63

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
d Elongation after rupture
d10 Elongation after rupture
y The relative narrowing
HB Brinell hardness number
HRC Rockwell hardness (indenter diamond spheroconical)

Physical characteristics

Temperature Е, HPa r, kg/m3 l, W/(m · °C) a, 10-6 1/°C С, J/(kg · °C)
0 204 7820 - - -
100 - - 78 125 -
200 - - 67 134 525
400 - - - 144 525
800 - - - 152 689

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
С Specific heat

Technological properties

Name The value
Weldability welded without restriction (except chemical-thermally treated parts). Welding methods: SMAW, Ads submerged arc and gas protection, the CCC without restriction.
Склонность к отпускной хрупкости tend not
The temperature of forging Start - 1260 °C, the end - 750 °C. the cross-Section up to 600 mm, with the recrystallization annealing (or normalizing), one hypothermia.
Flock-sensitive sensitivity not sensitive
Machinability In a normalized state in HB 143-187 Kn TV.SPL.=1.00 Kn b.St.=0.95
Microstructure The size of austenite grains in the steel should be not larger than 5 numbers according to GOST 5639.