Alloy 68NKHVKTJU (ЭП578)
Designation
| Name | The value |
|---|---|
| Designation GOST Cyrillic | 68НХВКТЮ |
| Designation GOST Latin | 68HXBKTJu |
| Transliteration | 68NHVKTYu |
| By chemical elements | 68NiCrВCoTeAl |
| Name | The value |
|---|---|
| Designation GOST Cyrillic | ЭП578 |
| Designation GOST Latin | EP578 |
| Transliteration | EhP578 |
| By chemical elements | - |
Description
Alloy 68NKHVKTJU used: for the manufacture of elastic sensing elements, operating at temperatures from -196 °C to +500 °C; details provocatively elements Aviapribor and automatic aviation systems.
Note
Alloy non-magnetic corrosion-resistant dispersion-hardened with a temporary resistance 1375- 1570 MN/m2 (140−160 kgf/mm2), with the normal elasticity modulus 196000- 216000 MN/m2 (20000- 22000 kgf/mm2).
Standards
| Name | Code | Standards |
|---|---|---|
| Classification, nomenclature and General rules | В30 | GOST 10994-74 |
| Tape | В34 | TU 14-1-4456-88 |
| Bars and shapes | В32 | TU 14-1-4470-88, TU 14-11-245-88 |
| Wire, steel, alloy | В73 | TU 14-1-4488-88 |
Chemical composition
| Standard | C | S | P | Mn | Cr | Si | Ni | Fe | Cu | Al | V | B | Ti | Nb | W | Ce | Co |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GOST 10994-74 | ≤0.05 | ≤0.01 | ≤0.015 | ≤0.4 | 18-20 | ≤0.4 | Rest | ≤1 | ≤0.07 | 1.3-1.8 | ≤0.2 | 0.003 | 2.7-3.2 | ≤0.2 | 9-10.5 | 0.05 | 5.5-6.7 |
Ni is the basis.
According to GOST 10994-74, the calculated content of boron and cerium is indicated.
According to TU 14-1-4470-88 and TU 14-1-4456-88 the chemical composition is given for the alloy 68NHVKTYU-VI (EP578-VI). The residual content of niobium and vanadium is not more than 0.20% of each. Boron and cerium are introduced by calculation.
According to GOST 10994-74, the calculated content of boron and cerium is indicated.
According to TU 14-1-4470-88 and TU 14-1-4456-88 the chemical composition is given for the alloy 68NHVKTYU-VI (EP578-VI). The residual content of niobium and vanadium is not more than 0.20% of each. Boron and cerium are introduced by calculation.
Mechanical properties
| Section, mm | sT|s0,2, MPa | σU, MPa | d5, % | d4 | y, % | KCU, kJ/m2 | HB, MPa | HRC | HV, MPa |
|---|---|---|---|---|---|---|---|---|---|
| Cold-rolled steel strip on the other 14-1-4456-88. Delivery condition - Dispersion hardening in a stepwise mode: 800 °C for 1 hour, 700 °C - 2 hours, air cooling | |||||||||
| - | - | ≥1470 | - | ≥1 | - | - | - | ≥46 | ≥460 |
| - | - | ≥1370 | - | ≥1.5 | - | - | - | ≥43 | ≥430 |
| The bars as supplied on the other 14-1-4470-88. Quenching in water from 1060-1100 °C + the Dispersion hardening at 790-810 °C (aging for 3.0-4.5 hours) + Dispersion hardening at 690-710 °C (extract 4-6 hours) | |||||||||
| 60, 65, 70 | ≥785 | ≥1180 | ≥15 | - | ≥20 | ≥396 | 321-415 | - | - |
| 8-55 | ≥835 | ≥1230 | ≥18 | - | ≥25 | ≥539 | 321-415 | - | - |
| 60-100 | ≥785 | ≥1180 | ≥15 | - | ≥20 | ≥396 | 321-415 | - | - |
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 |
| y | The relative narrowing |
| KCU | Toughness |
| HB | Brinell hardness number |
| HRC | Rockwell hardness (indenter diamond spheroconical) |
| HV | The Vickers hardness |
