Steel 25
Designation
| Name |
The value |
| Designation GOST Cyrillic |
25 |
| Designation GOST Latin |
25 |
| Transliteration |
25 |
| The 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 |
| Sectional and shaped rolling |
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 |
| Sectional and shaped rolling |
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 stripes |
В33 |
GOST 1577-93, GOST 4041-71, TU 14-1-1557-76, TU 14-1-4516-88 |
| Tapes |
В34 |
GOST 2284-79 |
| Pipes steel and connecting parts to them |
В62 |
GOST 3262-75, GOST 20295-85, GOST 24950-81, TU 14-3-1428-86 |
| Tapes |
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 stripes |
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 |
| Metal forming. Forgings |
В03 |
GOST 8479-70, OST 5Р.9125-84, ST ЦКБА 010-2004 |
| Bulls. Blanks. 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 |
Mechanical characteristics
| Section, mm |
sT|s0,2, MPa |
σB, MPa |
d5, % |
d4 |
d10 |
y, % |
kJ/m2, кДж/м2 |
Brinell hardness number, 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 |
| Section |
Section |
| sT|s0,2 |
Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2% |
| σB |
Limit short-term strength |
| d5 |
Elongation after rupture |
| d4 |
Elongation after rupture |
| d10 |
Elongation after rupture |
| y |
The relative narrowing |
| kJ/m2 |
Toughness |
| HRC |
Rockwell hardness (indenter diamond spheroconical) |
| HRB |
Rockwell hardness (indenter steel, spherical) |
Physical characteristics
| Temperature |
Е, ГПа |
G, ГПа |
r, кг/м3 |
l, Вт/(м · °С) |
R, НОм · м |
a, 10-6 1/°С |
С, Дж/(кг · °С) |
| 0 |
198 |
81 |
7820 |
- |
169 |
- |
- |
| 20 |
198 |
- |
7820 |
- |
169 |
- |
- |
| 100 |
196 |
80 |
- |
51 |
219 |
122 |
470 |
| 200 |
191 |
76 |
- |
49 |
292 |
13 |
470 |
| 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 |
| 800 |
- |
- |
- |
26 |
- |
127 |
- |
| 900 |
- |
- |
- |
27 |
- |
- |
- |
| 1000 |
- |
- |
- |
- |
- |
124 |
- |
| 1200 |
- |
- |
- |
- |
- |
134 |
- |
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. |
| Propensity to temper brittleness |
tend not |
| Forging temperature |
Start - 1280 °C, end - 700 °C. air Cooling. |
| Flock-sensitive sensitivity |
not sensitive |
| Workability by cutting |
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. |