A
PDF file with full details of the Allectra products as well as a price
list are are available via e-mail
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| USA
AISI |
BS
EN |
C
max |
Cr |
Ni |
Mo |
N |
Comments |
Suitability
for UHV |
| |
|
|
|
|
|
|
|
|
| 304 |
1.4301 |
0.08 |
18.20 |
18.20 |
- |
- |
General
purpose, relatively low cost |
medium |
| |
|
|
|
|
|
|
|
| 304L |
1.4306 |
0.03 |
18.20 |
8.12 |
- |
- |
Extra
low C prevents carbide precipitation - recommended for general UHV use |
good |
| |
|
|
|
|
|
|
|
| 304LN |
1.4311 |
0.03 |
18.50 |
9.50 |
- |
0.18 |
Improved
mechanical properties over 304L |
good |
| |
|
|
|
|
|
|
|
| 316 |
1.4401 |
0.08 |
16.18 |
10.14 |
2.30 |
- |
General purpose but good corrosion resistance |
good |
| |
|
|
|
|
|
|
|
| 316L |
1.4404 |
0.03 |
16.18 |
10.14 |
2.30 |
- |
Extra
low carbon - good TIG welding properties, highest corrosion resistance
especially to chlorides, magnetic permeability less than 1.005 |
excellent |
| |
|
|
|
|
|
|
|
| 316LN |
1.4406 |
0.07 |
17.18 |
10.13 |
2.50 |
0.20 |
Extra
low carbon - good TIG welding properties, highest corrosion resistance
especially to chlorides, magnetic permeability less than 1.005, better
mechanical properties than 316L |
excellent |
| |
|
|
|
|
|
|
|
| 321 |
1.4541 |
0.08 |
17.19 |
9.12 |
- |
- |
General
purpose including bellows |
good |
| |
|
|
|
|
|
|
|
Ideally
316LN is the best material for UHV use. It has low magnetic permeability, ease
of working by machine and resistance to changes during working are all very
important. Additionally it is recognised as having better than average resistance
to corrosive gases including chlorine. However, it is a very expensive material
and difficult to obtain in tube or sheet form.
The
best compromise material for UHV is 316L which has very nearly the same properties
as 316LN but is readily available . The corrosion resistance of 316L is very
good while its magnetic permeability is less than 1.005 (Yadev 2001) and it
can be regarded as non magnetic except in extremely demanding situations.
Caburn
UHV limited recommends the Allectra series of UHV flanges and fittings which
are manufactured entirely from 316L stainless steel.
Reference
S Yadev, Fermilab Report, TD-01-065, September 2001
Fermi National Accelerator,
PO Box 500, Batavia, Illinois, USA 60510
Electrical
feedthroughs and connectors
Optical
quality quartz viewports
In-vacuum
stepper motors
UHV
chambers in stainless steel, Mu-Metal and aluminium
UHV
flanges and fittings in 316L stainless steel for low residual magnetic permeability
and increased resistance to corrosive gases
Wire
and accessories
Allectra offers high quality UHV and high vacuum components
