Alloy 25НЮ
Designation
| Name |
The value |
| Designation GOST Cyrillic |
25НЮ |
| Designation GOST Latin |
25HJu |
| Transliteration |
25NYu |
| The chemical elements |
25NiAl |
Description
Alloy 25НЮ used: for the manufacture of cast (with subsequent grinding) permanent magnets mass production (due to otsutstvie scarce and expensive cobalt).
Standards
| Name |
Code |
Standards |
| Sheets and stripes |
В33 |
TU 14-1-157-72 |
Chemical composition
| Standard |
C |
Mn |
Si |
Ni |
Fe |
Al |
Nb |
| TU 14-1-157-72 |
≤0.05 |
≤0.6 |
≤0.4 |
24.5-25.5 |
The rest |
8.4-9.6 |
3.7-4.2 |
Fe is the basis.
Technological properties
| Name |
The value |
| Features of production |
The main drawbacks of alloy: high hardness, brittleness and poor workability, so the magnets of them have cast manufacturing and processing by grinding. Alloy not processed by cutting, not drilled. Products accurate dimensions, due to brittleness and hardness, allowing processing only by grinding to produce almost impossible. Fine products made by powder metallurgy methods, obtaining sintered magnets by compaction of the powder composed of the crushed particulate alloy, and further sintering at high temperatures by analogy with the processes of ceramics. Pressed parts sintered in a tubular electric furnace at a temperature 1280-1290 °C (delay 2-3 hours), cooled in running water. Sintering is produced in the environment of the reducing gas of hydrogen or dissociated ammonia. |
