Ti6Al4V vs. Aluminum Alloy in steam sterilization
Ti6Al4V vs. Aluminum Alloy in steam sterilization
(OP)
I've been searching for an answer to this with only finding a few hints and little else.
I'm in the process of laying out a steam sterlization case and generally the individual components (SS instruments, titanium implants) are segregated from other metal contact thru either silicone or vinyl coated brackets. Most of our previous cases employ a screw rack that is vinyl coated aluminum--presumably for both aesthetics and galvanic corrosion protection.
This particular project is low-quantity, so in the interest of possible cost reductions the manufacturer suggested creating this part out of bare (no vinyl coating) aluminum alloy sheet (I'm not sure which, I'd guess 60xx)--possibly anodized if that was preferred. My question is--these titanium screws will be in minor contact with this rack during multiple steam sterilization cycles at the hospital (270 deg. F for 6 min.); what sort of corrosion should be expected?
From what I've read the aluminum should corrode preferentially but I've also read that the titanium could absorb some hydrogen in the process and eventually suffer from hydrogen embrittlement--but in both those cases I believe the environment was highly acidic.
No corrosion is obviously preferred; the Titanium needs to retain it's material properties even if the aluminum slowly erodes to nothing.
I'm in the process of laying out a steam sterlization case and generally the individual components (SS instruments, titanium implants) are segregated from other metal contact thru either silicone or vinyl coated brackets. Most of our previous cases employ a screw rack that is vinyl coated aluminum--presumably for both aesthetics and galvanic corrosion protection.
This particular project is low-quantity, so in the interest of possible cost reductions the manufacturer suggested creating this part out of bare (no vinyl coating) aluminum alloy sheet (I'm not sure which, I'd guess 60xx)--possibly anodized if that was preferred. My question is--these titanium screws will be in minor contact with this rack during multiple steam sterilization cycles at the hospital (270 deg. F for 6 min.); what sort of corrosion should be expected?
From what I've read the aluminum should corrode preferentially but I've also read that the titanium could absorb some hydrogen in the process and eventually suffer from hydrogen embrittlement--but in both those cases I believe the environment was highly acidic.
No corrosion is obviously preferred; the Titanium needs to retain it's material properties even if the aluminum slowly erodes to nothing.





RE: Ti6Al4V vs. Aluminum Alloy in steam sterilization
For the aluminium, use a low copper concentration to minimize corrosion.
Regards,
Cory
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RE: Ti6Al4V vs. Aluminum Alloy in steam sterilization
I personally agree with you based on the likelyhood of this having occured in the past due to vinyl wear and tear exposing aluminum on our different [old] existing racks and the [to my knowledge] absence of any failures in a mode that would be described by brittleness at the area of contact with the rack--doesn't eliminate the concern, however.
RE: Ti6Al4V vs. Aluminum Alloy in steam sterilization
Regards,
Cory
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips Fora.
RE: Ti6Al4V vs. Aluminum Alloy in steam sterilization
RE: Ti6Al4V vs. Aluminum Alloy in steam sterilization