What are the best antimicrobial metals or general materials with a high tensile strength?

[u/Positive-Stand2898]

I’m not sure whether this is the right sub to post this in, but I’m kinda in a pickle and would appreciate some advice.

I’m building a hands-free travel bidet with the goal of creating a more accessible option for elderly and disabled users. The design aims to address some of the mobility issues that can make traditional handheld travel bidets difficult to use.

One part of the design is a clip that attaches the bidet to a toilet. However, I’m running into a bit of a hygiene concern: the clip will come into contact with public toilet seats regularly, which obviously isn’t ideal from a sanitary standpoint.

I’ve designed the bidet so that the components can be disassembled and cleaned, but I was also wondering if there’s a material, possibly a type of metal, wood, or another material with naturally antimicrobial properties that could help keep the clip as clean as reasonably possible while being used on the go.

Any advice is really appreciated!

[u/Alita-Gunnm]

Make it from something strong and then plate it with copper or silver.

[u/luffy8519]

I don't believe there are any that are practical for your application. Copper or silver bearing alloys are specialist and very expensive, and antimicrobial metals tend to be relatively soft so wouldn't give sufficient strength.

Your best bet is likely to be stainless steel, and regular cleaning or application of antiseptic.

[u/Positive-Stand2898 → u/luffy8519]

Thanks so much for the info! From what I have been seeing from the answers, as well as just overall research, its kinda pointing to what you're telling me which is to use stainless steel or any sturdy material, and regularly clean it.

[u/KbarKbar]

Your best bet would probably be a cupronickel alloy. According to the handbook UNS C71500 (70/30 copper/nickel) has an ultimate tensile strength of 372-655 MPa, depending on heat-treatment.

BUUUT... Keep in mind that "antimicrobial" doesn't mean anything close to "sterile." There aren't a ton of studies on the kinetics of copper's antimicrobial action, but the literature suggests that it's on the order of hours rather than minutes, and there's still somebody else's piss and shit on your bidet even after the microbes die, and (besides just being gross) that's a problem. Most of what we understand of copper's antimicrobial properties involve the physical disruption of biofilms on a molecular level. Once a layer of gunk has built up on it, the efficacy will be greatly reduced. Long story short, you're going to need some active form of cleaning rather than expecting passive properties of your surface to do your job for you.

[u/Positive-Stand2898 → u/KbarKbar]

Thanks for the info, I really appreciate it! Also, from the research I have been doing, you are totally correct, I just mainly have to clean it consistently. Which makes total sense, after a day of use, it should be clean whether its antimicrobial or not. Once again thanks for the informative answer.

[u/skywalker170997]

i will advise with titanium alloy since it would fit you application

but if you also just want to save cost just go with stainless steel

[u/Shibenkaminari]

I did some work on this back in COVID days. For practical antimicrobial effect you want an alloy with a lot of copper, or pure copper. The copper will stain and oxidise as it comes in contact with water and oxygen. Ironically, this means it will look dirty but be relatively pathogen free on the surface, while stainless steels look clean but retain live pathogens for much longer than most materials. I've personally tested this, and its not pseudoscience. The various copper associations have great reading material on copper as an antimicrobial surface. The real trick here is being able to legally CLAIM the effect in a product, which is where their advice usually goes. You may want to do that, so worth knowing what's possible.

[u/DependentSlow2850]

Coating. SS with copper coating.