Tu 48-19-309-79. Wire made of thoriated tungsten. Technical conditions.
Are you interested in TU 48−19−309−79 «Toroidal tungsten wire «from the supplier company AvecGlob? Here you will find interesting information on this topic.
Application area
These specifications extend to a drawn wire made of thoriated tungsten, obtained by the powder metallurgy method, which is used in the manufacture of electronic devices.
The range of wires depends on the composition of the additives and is determined by the brands that are given in the table
| Brand of tungsten | Characteristic |
| VM | Form-resistant (non-dormant) up to 2100 ° C tungsten with siliceous and thorium additives having a high recrystallization temperature and characterized in the recrystallized state by a coarse-crystalline structure and increased strength under impact loads and vibrations. |
| VT-7, VT-10, VT-15 | Tungsten with a dopant of thorium dioxide, which has increased emission and strength properties at high temperatures, characterized by a fine-crystalline structure in a recrystallized state. |
Tungsten wire is supplied in a state (Group A) of grade 1 that is not cleaned from the technological lubrication. The purpose and output diameter of the wire, depending on the brand, are indicated in the table
| Brand of tungsten | Diameter of wire, micron | Appointment |
| VM | from 18.5 to 1500 | Parts of devices operating at a temperature of not more than 2100 ° C in conditions of increased mechanical loads (shocks, vibrations). |
| VT-7 | from 25 to 1500 | Hooks, springs, as well as cathodes of some Electrical and gas-discharge devices. |
| VT-10 | from 25 to 1500 | Cathodes of electronic and gas-discharge devices. |
| VT-15 | from 150 to 1500 | Also |
Supplier — AvekGlob Company — offers at a reasonable price from the manufacturer a toroidal tungsten wire of various diameters, which meets the requirements of TU 48−19−309−79. The supplier guarantees the timely delivery of products to any address specified by the consumer.
Assortment and tolerances
The nominal wire diameter and allowable deviations from it must correspond to the data in the table
| Range of diameters, μm | Permissible deviations by weight,% | Tolerances allowed by diameter |
| from 18.5 to 39.5 every 0.5 | ± 2.5 | - |
| from 40 to 79 every 1 | ± 2 | - |
| from 80 to 178 every 2 | ± 1.5 | - |
| from 180 to 285 every 5 | ± 1.5 | - |
| from 290 to 355 every 5 | ± 1.0 | - |
| from 360 to 590 every 10 | - | ± 1 |
| from 600 to 1040 every 20 | - | ± 1.5 |
| from 1050 to 1500 every 50 | - | ± 1.5 |
Technical requirements for the composition
The chemical composition of the wire should correspond to that given in the table
| Brand of tungsten | Content of tungsten (including thorium oxide),%, not less than | Content of impurities,%, not more than | Oxide content thorium,% |
| VM | 99.95 | 0.05 | 0.17… 0.25 |
| VT-7 | 99.95 | 0.05 | 0.7… 1 |
| VT-10 | 99.95 | 0.05 | 1… 1.5 |
| VT-15 | 99.95 | 0.05 | 1.5… 2 |
Wire cross section must be round. Ovality within tolerance for diameter is allowed. There should be no oxidation marks on the surface of the wire. Wire with a diameter of less than 500 microns should have a color from black to dark gray. On a wire with a diameter of 500 μm or more, weak colors of tarnishing are allowed. Wire should not have burrs, stratification and cracks. On a wire with a diameter of 500 μm or more, the presence of strokes, small burrs visible to the naked eye, but not leading the wire beyond the diameter tolerance, is allowed. A wire with a diameter of 1000 to 1500 μm should not have stratification.
Supplier — AvekGlob Company — offers to purchase various profiles of wire, which is made of thoriated tungsten, and meets the requirements of TU 48−19−309−79… Products can be bought at a price formed on the basis of European and world standards of production. Implementation is possible in bulk and retail, for regular customers, there is a flexible system of discounts