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. |