galling in vacuum environment
galling in vacuum environment
(OP)
Hi,
I'm designing some parts that are to be fitted into a high vacuum system. They consist of a large (5 inch diameter) threaded part (like a bolt)and a mating nut-materials need to be stainless steel type. I have been planning on using Nitronic 60 for one of the parts but am not sure about the other. The Armco bulletin for nitronic (link below) indicates in table 1 that there is no difference for 440C, 303, 304, 17-4 (no HT specified) or self mated. Do any of you have experience with these materials in a vacuum? I was planning on trying a dry film lube (type TBD) as well. There is some high temp (250 F) exposure for a bake out period. The parts need to be infrequently disassembled, hence my concern about galling.
http ://hpalloy .com/alloy s/descript ions/NITRO NIC60.html
Thanks,
Bob
I'm designing some parts that are to be fitted into a high vacuum system. They consist of a large (5 inch diameter) threaded part (like a bolt)and a mating nut-materials need to be stainless steel type. I have been planning on using Nitronic 60 for one of the parts but am not sure about the other. The Armco bulletin for nitronic (link below) indicates in table 1 that there is no difference for 440C, 303, 304, 17-4 (no HT specified) or self mated. Do any of you have experience with these materials in a vacuum? I was planning on trying a dry film lube (type TBD) as well. There is some high temp (250 F) exposure for a bake out period. The parts need to be infrequently disassembled, hence my concern about galling.
http
Thanks,
Bob





RE: galling in vacuum environment
In previous experience with other alloys, a good dry film anti-gall/anti-sieze for vacuum oven use is powdered boron nitride, either aerosol spray or made into a water paste and brushed on.
RE: galling in vacuum environment
RE: galling in vacuum environment
I agree with Uncle Syd. Austenite Nitronic 60 is ideal, both surfaces. Not just for wear or galling, but to avoid electrochemical reaction of dissimilar metal, or metallurgical counter-face solubility.
Soft alloyed metals, like lead with tin or copper, applied electrolytically, could work. A good choice for low friction, especially when used at higher temperature, or under vacuum.
If you're considering dry film lubrication, stay inorganic, binder and all. Here, to help you: <a href="ht
I wish you well!
William Gunnar
http://www.IndustrialCoatingsWorld.com
RE: galling in vacuum environment
Bob