Without knowing your application, it is a bit tough to suggest a
non-metallic material such as an oxide/non-oxide ceramic or polymer.
Also, depending on cost several more exotic options may exist. A litte
more detail and the suggestions will abound.
The screws are intended to tighten two plates with a narrow channel of fluid
flowing in between. As the ineternal pressure can be up to 2 atm, i'm
sourcing for screws that can withstand this load. As for why the need to be
non-metallic, it is to avoid interference with instruments.
magnetic. u probably guessed it. we're going to conduct experiments using
mri. so the material has to be non ferro, para magnetic. To be on the safe
side, i would prefer polymeric materials. Peek might be ok, but i'm not
sure. Is there anything that has a higher tensile strength than peek? Of
course, it must be available off the shelf...
Depending on how many of the screws you have to bolt the platens and
their diameter several choices could exist. One option would be the
polymer route which would also be the most cost effective particularly
with molded thermoplastics. Further carbon fiber reinforced polymers
would add significant strength, but you would probably have to have
On the ceramic side there are also several choices. Aluminum oxide
ceramics can be machined into various bolts and screws and there are
several manufacturers that do this sort of work, but for added
toughness SiC screws would probably be the best choice. I had several
1/4" Silicon carbide bolts fabricated several years back for a high
temperature testing rig and while always using appropriate tighting
torque never broke a single one.
You didn't specify the diameter. I have found that the nylon bolts used
to hold down toilet seats to the toilet hold up quite well. Another
possibility are the nylon screws used to fasten license plates to cars.
They truly take a beating and hold tightly for years. And all are