Designation
Name |
The value |
Designation GOST Cyrillic |
25 |
Designation GOST Latin |
25 |
Transliteration |
25 |
By chemical elements |
25 |
Description
25 steel is used: for the manufacture of sheet metal, 1−2 mm 4−14 category, intended for cold forming; axes, shafts (including ship), couplings, dogs, levers, plugs, washers, rollers, bolts, flanges, tees, fasteners and other neotectonic components; screws, bushings, dogs and other details, which are requirements of high surface hardness and wear resistance at low strength core (after chemical-thermal treatment (HTO); details of pipeline valves (after hardening); solid-rolled rings for different purposes.
Note
The degree of deoxidation — SP.
Standards
Name |
Code |
Standards |
Bars and shapes |
В32 |
GOST 1050-88, GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 10702-78, GOST 14955-77, GOST 1050-2013, OST 1 92049-76, TU 14-1-5414-2001, TU 14-1-2118-77, TU 14-1-3651-83, TU 14-1-4597-89, 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 8239-89, GOST 8240-97, GOST 8278-83, GOST 8281-80, GOST 8282-83, GOST 8283-93, GOST 8319.0-75, GOST 8509-93, GOST 8510-86, GOST 9234-74, GOST 11474-76, GOST 2590-2006, GOST 2591-2006, GOST 2879-2006, OST 5.9087-84, TU 14-2-341-78 |
Sheets and strips |
В33 |
GOST 1577-93, GOST 4041-71, TU 14-1-1557-76, TU 14-1-4516-88 |
Tape |
В34 |
GOST 2284-79 |
Steel pipes and fittings to them |
В62 |
GOST 3262-75, GOST 20295-85, GOST 24950-81, TU 14-3-1428-86 |
Tape |
В24 |
GOST 3560-73 |
Steel wire medium and high carbon |
В72 |
GOST 3920-70, GOST 7372-79, GOST 9389-75, GOST 9850-72, GOST 17305-91, GOST 26366-84 |
Low carbon steel wire |
В71 |
GOST 5663-79 |
Sheets and strips |
В23 |
GOST 82-70, GOST 14918-80, GOST 16523-97, GOST 16523-89, GOST 16523-70, GOST 103-2006, GOST 19903-90, TU 14-1-1934-76, TU 14-1-4632-93 |
Processing of metals by pressure. Forgings |
В03 |
GOST 8479-70, OST 5Р.9125-84, ST ЦКБА 010-2004 |
Blanks. Of the workpiece. Slabs |
В31 |
OST 3-1686-90, TU 108.1461-87, TU 14-1-4944-90, TU 1-92-156-90 |
Thermal and thermochemical treatment of metals |
В04 |
ST ЦКБА 026-2005 |
Chemical composition
Standard |
C |
S |
P |
Mn |
Cr |
Si |
Ni |
Fe |
N |
As |
GOST 1050-88 |
0.22-0.3 |
≤0.04 |
≤0.035 |
0.5-0.8 |
≤0.25 |
0.17-0.37 |
≤0.3 |
Rest |
≤0.006 |
≤0.08 |
GOST 10702-78 |
0.22-0.3 |
≤0.04 |
≤0.035 |
≤0.6 |
≤0.25 |
≤0.2 |
≤0.3 |
Rest |
≤0.006 |
≤0.08 |
Fe is the basis.
According to GOST 1050-88, the nitrogen content is specified for the steel of the oxygen-converter method of smelting. For all other types of smelting, the nitrogen content was N≤0.008%.
Mechanical properties
Section, mm |
sT|s0,2, MPa |
σU, MPa |
d5, % |
d4 |
d10 |
y, % |
KCU, kJ/m2 |
HB, MPa |
HRC |
HRB |
Rolled sheet 1-2 categories of heat-treated (annealing, normalization, high tempering or normalizing + tempering) in the delivery state according to GOST 4041-71 |
4-14 |
- |
390-540 |
≥26 |
- |
≥23 |
- |
- |
≤138 |
- |
≤76 |
Wire for cold heading as supplied by GOST 5663-79 |
- |
- |
470-620 |
- |
- |
- |
≥55 |
- |
- |
- |
- |
- |
- |
≤640 |
- |
- |
- |
≥50 |
- |
- |
- |
- |
Hot-rolled steel and hot rolled with special surface finish |
- |
- |
- |
- |
- |
- |
- |
- |
≤170 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
≤156 |
- |
- |
Steel calibrated and calibrated with special surface finish |
- |
- |
≥540 |
≥7 |
- |
- |
≥40 |
- |
≤217 |
- |
- |
- |
- |
≤540 |
- |
- |
- |
≥50 |
- |
≤170 |
- |
- |
- |
- |
≤490 |
- |
- |
- |
≥50 |
- |
≤170 |
- |
- |
Forgings. Normalization at 880-900 °C |
|
≥275 |
≥450 |
≥23 |
- |
- |
≥55 |
≥882 |
121-171 |
- |
- |
Cold-rolled steel strip of 0.1-4.0 mm in the delivery state according to GOST 2284-79 |
- |
- |
540-880 |
- |
- |
- |
- |
- |
- |
- |
- |
- |
- |
340-590 |
- |
≥18 |
- |
- |
- |
- |
- |
- |
- |
- |
340-540 |
- |
≥18 |
- |
- |
- |
- |
- |
- |
Steel, hot-rolled, forged, calibrated and silverfish 2nd category after normalization |
- |
- |
≥450 |
≥23 |
- |
- |
≥50 |
- |
- |
- |
- |
Steel grooved 5-th category after annealing or high holidays |
- |
- |
≤410 |
≥19 |
- |
- |
≥50 |
- |
- |
- |
- |
Ring forged in OST 1 92049-76. Normalization |
25 |
≥255 |
≥430 |
≥17 |
- |
- |
≥40 |
≥686 |
- |
- |
- |
Forgings. Hardening + Vacation |
100-300 |
≥275 |
≥530 |
≥17 |
- |
- |
≥38 |
≥334 |
156-197 |
- |
- |
Blank pieces of pipe fittings. Extract at 890-910 °C (2.5-4.0 hours depending on the thickness and weight of the workpiece) annealing in air |
≤100 |
≥245 |
≥470 |
≥22 |
- |
- |
≥48 |
≥481 |
143-179 |
- |
- |
100-300 |
≥215 |
≥390 |
≥20 |
- |
- |
≥48 |
≥481 |
123-167 |
- |
- |
Hot-rolled strip. Normalization |
- |
- |
≥450 |
≥23 |
- |
- |
≥50 |
- |
- |
- |
- |
Forgings. Hardening + vacation + normalization |
100-300 |
≥175 |
≥350 |
≥24 |
- |
- |
≥50 |
≥579 |
101-143 |
- |
- |
300-500 |
≥175 |
≥350 |
≥22 |
- |
- |
≥45 |
≥579 |
101-143 |
- |
- |
100 |
≥175 |
≥350 |
≥28 |
- |
- |
≥55 |
≥628 |
101-143 |
- |
- |
100-300 |
≥195 |
≥390 |
≥23 |
- |
- |
≥50 |
≥530 |
111-156 |
- |
- |
300-500 |
≥195 |
≥390 |
≥20 |
- |
- |
≥45 |
≥481 |
111-156 |
- |
- |
100 |
≥195 |
≥390 |
≥26 |
- |
- |
≥55 |
≥579 |
111-156 |
- |
- |
100-300 |
≥215 |
≥430 |
≥20 |
- |
- |
≥48 |
≥481 |
123-167 |
- |
- |
100 |
≥215 |
≥430 |
≥24 |
- |
- |
≥53 |
≥530 |
123-167 |
- |
- |
100 |
≥245 |
≥470 |
≥22 |
- |
- |
≥48 |
≥481 |
143-179 |
- |
- |
Sheet 1 and 2 categories |
|
- |
390-540 |
≥26 |
- |
- |
- |
- |
- |
- |
- |
Hot-rolled sheet in the delivery condition. Group strength К390В |
≤2 |
- |
390-590 |
- |
≥19 |
- |
- |
- |
- |
- |
- |
2-3.9 |
- |
390-590 |
- |
≥20 |
- |
- |
- |
- |
- |
- |
Cold-rolled sheet in the delivery condition. Group strength К390В |
≤2 |
- |
390-590 |
- |
≥20 |
- |
- |
- |
- |
- |
- |
2-3.9 |
- |
390-590 |
- |
≥21 |
- |
- |
- |
- |
- |
- |
Cementation at 920-950 °C + quenching in water from 820-840 °C + vacation at 180-200 °C, air cooling |
50 |
≥345 |
≥550 |
≥25 |
- |
- |
≥45 |
- |
≥170 |
55-63 |
- |
A sample with a diameter of 6 mm and a length of 30 mm, laminated. The rate of deformation of 16 mm/min strain Rate of 0.009 1/s |
- |
≥130 |
≥145 |
≥42 |
- |
- |
≥77 |
- |
- |
- |
- |
- |
≥69 |
≥96 |
≥57 |
- |
- |
≥78 |
- |
- |
- |
- |
- |
≥47 |
≥79 |
≥53 |
- |
- |
≥95 |
- |
- |
- |
- |
- |
≥40 |
≥54 |
≥60 |
- |
- |
≥100 |
- |
- |
- |
- |
- |
≥24 |
≥38 |
≥66 |
- |
- |
≥100 |
- |
- |
- |
- |
- |
≥14 |
≥23 |
≥101 |
- |
- |
≥100 |
- |
- |
- |
- |
- |
≥20 |
≥25 |
≥67 |
- |
- |
≥100 |
- |
- |
- |
- |
After rolling. The rate of deformation of 0.8 mm/min. |
- |
≥310 |
≥490 |
- |
- |
≥28 |
≥58 |
≥765 |
- |
- |
- |
- |
≥320 |
≥560 |
- |
- |
≥13 |
≥44 |
≥952 |
- |
- |
- |
- |
≥200 |
≥540 |
- |
- |
≥22 |
≥57 |
≥863 |
- |
- |
- |
- |
≥165 |
≥465 |
- |
- |
≥25 |
≥66 |
≥677 |
- |
- |
- |
- |
≥150 |
≥330 |
- |
- |
≥28 |
≥70 |
≥481 |
- |
- |
- |
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 |
d4 |
Elongation after rupture |
d10 |
Elongation after rupture |
y |
The relative narrowing |
KCU |
Toughness |
HB |
Brinell hardness number |
HRC |
Rockwell hardness (indenter diamond spheroconical) |
HRB |
Rockwell hardness (indenter steel, spherical) |
Physical characteristics
Temperature |
Е, HPa |
G, HPa |
l, W/(m · °C) |
R, Mr. · m |
a, 10-6 1/°C |
С, J/(kg · °C) |
300 |
186 |
73 |
46 |
381 |
137 |
483 |
400 |
163 |
70 |
43 |
488 |
143 |
521 |
500 |
- |
66 |
40 |
601 |
147 |
521 |
600 |
- |
61 |
36 |
758 |
15 |
- |
700 |
- |
- |
32 |
925 |
152 |
571 |
A description of the physical symbols
Name |
Description |
Е |
The normal elasticity modulus |
r |
Density |
l |
Coefficient of thermal conductivity |
R |
UD. the resistivity |
a |
The coefficient of linear expansion |
Technological properties
Name |
The value |
Weldability |
Welded without restriction, except detali after HTO. The welding methods of SMAW, ADS submerged arc and gas protection, the CCC. |
Склонность к отпускной хрупкости |
tend not |
The temperature of forging |
Start - 1280 °C, end - 700 °C. air Cooling. |
Flock-sensitive sensitivity |
not sensitive |
Machinability |
In the hot rolled condition when blower SB=450-490 MPa Kn TV.SPL.=1.7 Kn b.St.=1.6 |
Surfacing |
Surfacing of sealing surfaces of valves in accordance with OST 26-07-2028-81 is made by manual arc welding electrodes type e-20X13 with plaster SSSI-13НЖ, NII-48, NII-48Ж-1 or SV wire-12H13 or SV-20X13. Surface preparation for overlay welding is performed by machining. Surfacing is performed with preliminary and accompanying heating to 400-450 °C is not less than 3 layers with thickness not less than 4 mm, excluding allowance for machining. Heat treatment after welding is produced by tempering at 550-600 °C (delay of 2-5 h) hardness HB=301-350, at 600-650 °C (delay of 2-5 h) hardness HB=240 to 300, at 400-450 °C (delay of 2-5 h) hardness HB=351-400. The temperature of the furnace when loading the details for the home should be no more than 300 °C. |