How to prevent galvanic corrosion in carbon composites

Рет қаралды 19,875

5 жыл бұрын

Some thoughts about galavic corrosion and its prevention in carbon composites with metal inserts are presented. A simple method to control if a pice is endangered of galvanic corrosion is shown. We exemplifly with #hortenmicrolight's control levers, which are a carbon and PVC-foam sandwich with usual steel bearings.

Пікірлер: 59

@latata381 Ай бұрын

Excellent video

@stef2465 2 ай бұрын

Exactly what I was looking for, thanks!

@tlangdon12 3 жыл бұрын

Great video. I didn't know that there was a chance of galvanic corrosion between Carbon Fibre and Steel. Thank you for explaining your solution as well explaining about the problem.

@tcsbodyworks 4 жыл бұрын

Thank you for sharing the information. Don't worry about it being a spoken video - keep up the great work!

@ctoforhire 4 жыл бұрын

Wow, something I never even thought about! Thanks for posting :)

@jeremyplatt 4 жыл бұрын

Very cool to see you testing them like this! I have used glass like this in the past but great to run and test and make sure it is isolated - great work.

@danielmiller2886 3 жыл бұрын

Great information, thank you! Even though English is not your first language, you communicated your point very well.

@miamatti 3 жыл бұрын

great video, thanks for sharing. I look forward to more videos in the future

@LindyDesignLab 5 жыл бұрын

Interesting, thanks for explaining.

@ladraode9dedos409 4 жыл бұрын

Thank you very much for that clarification!

@ChicagoRacerJoe 5 жыл бұрын

Excellent! Thank you for sharing.

@richarddixson1971 3 жыл бұрын

Ahhh! as someone whom has performed and tested cathodic protection and grounding systems, along with passivation of metalic componats, I have the feeling you are falling into a rabbit hole. I have also worked with carbon fiber laced with copper for faraday cage properties. If you have the slightest failure in your insulator, you will focus your cathodic reaction. I feel you should take advantage of the conductance of your carbon. I feel you may want to consider "How and What' you use to seat your metalic componants and what these parts are made of. I.E. Stainless Steel bearing parts with the proper lubricants will mitigate your reactions. Love the idea, thanks for taking your time!! you got me thinking! Test! Want to test your ideas! set up a basic DYI copper, silver, nickle plating system, cheap, maybe interesting? ROCK ON! Gett'[er Dun!

@VinothKumar-qo7ry 4 жыл бұрын

Thank you sor for sharing knowledgeable

@localhawk1 5 жыл бұрын

Thank you for the explanation

@Dlgeis 2 жыл бұрын

Great job

@carbonarne675 5 жыл бұрын

Great again

@lpleijsier5145 Жыл бұрын

very helpful thanks

@binarumah 5 ай бұрын

Hi Andres. Thank you for you video. Very good testing and explanation. I'm seeking your advice whether is it possible to bond metal steel with carbon?

@bonovoxel7527 Жыл бұрын

Very interesting, thanks! Does kevlar fibres conduct or is the same than fiberglass? Now that I'm aware I thought of using that because of its superior resistance to abrasion, i suppose better than fiberglass too.

@TheCrazySpanishGirl Жыл бұрын

Ok, so the main point is electric isolation between those two components... Good explanation. Thanks.

@sebastianllanos3052 3 жыл бұрын

!!!!! perfect

@smoothy8464 2 жыл бұрын

Great video.Those are the, not so well known characteristics of mixing construction materials.Add H2O/moisture from the road/air to the mix and you have an actual battery. H2O acts as a catalyst accelerating the corrosion, deterioration and eventual material separation.A reality in other fields as well such as, auto racing and high end bicycle manufacturing.

@JoshuaCussins Жыл бұрын

would it be a good idea to layer the inside of a carbon fiber fuel tank with fine fiber glass to prevent explosion?

@ready-to-race Жыл бұрын

Thank you for the video! Do you have an example on any parts with galvanic corrosion? I'm looking for some photos or video as some evidence that corrosion is an issue in discussion I had.

@andreschavarria1450 Жыл бұрын

You find many examples by searching the web. For example: www.compositesworld.com/articles/-optimizing-fasteners-for-cfrp-automotive-parts I know that galvanic corrosion was a big issue in german sailplanes after carbon composites were introduced.

@ramonbs6075 Жыл бұрын

Nice! Can you show how to isolate with glass fiber? Thx!

@anneandkent 5 жыл бұрын

Thanks for sharing. Does the glass/epoxy insulator help keep the bearings in place? For non-CNC parts, can you use interlay glass fiber during the layup process in pockets we’re your parts interface with metals, or is it better to add the glass after part is cured?

@andreschavarria1450 5 жыл бұрын

Yes, it keeps the bearings in place. If thin slowly curing epoxy is used, the border of the bearing is perfectly wetted ending in an excellent and strong fit. Defat the surfaces with isopropyl alcohol before. I think it is much easier to cover the surface after the part is cured. It's harder to guarantee that the parts are truly galvanically isolated when working on the wet layup. A couple of thin carbonfiber strands sufficie to connect the parts.

@andre9552 2 жыл бұрын

Probably the most helpful video on carbon galvanic corrosion, n ngl this should have been obvious to me but yea didn’t connect the dots so yea 😭😂

@mdmkoopman 5 жыл бұрын

Did you build the carbon arms, and then glued in the fibreglass sheet? Or is it build into the laminate?

@andreschavarria1450 5 жыл бұрын

The arms are first made, and just before the bearings are installed, a thin sheet of glass fabric is put between bearing and lever arm. Doing it in one shot, would be much more elaborate.

@DiegoAEscobedo 4 жыл бұрын

Andrés muy buenos videos, gracias. Por casualidad sos Argentino?

@andreschavarria1450 4 жыл бұрын

Gracias, Diego. Soy latino pero no Argentino :)

@carywhozawhastit2024 5 жыл бұрын

So use some glass fiber and epoxy as a barrier, thanks! Any chance you can show the technique you used?

@andreschavarria1450 5 жыл бұрын

I'll try to make a video next time. The process is quite simple: pre cut glass fiber, defat parts and resinate.

@emrage 4 жыл бұрын

How to you achieve tolerances for the bearing housing after laying the ID with glass fibre please? Or do you just press fit when bearing is cold?

@andreschavarria1450 4 жыл бұрын

The bearing is glued into the housing with the same expoxy resin used for lamination. No preload is created so that the internal clearance of the bearing should be small. We have a video about making these bellcranks, which shows the process in detail: kzfaq.info/get/bejne/b7l7nZydxsXXp4U.html

@6thgen.k 10 ай бұрын

How may i prevent ic corrosion on my carbon fiber infusion im doing on my ek chassis interior????

@ricobass0253 Жыл бұрын

How do you get conduction through the epoxy resin which is impregnated throughout the fibres?

@andreschavarria1450 Жыл бұрын

You do not have to do anything to get conduction. The carbon fibers touch each other, so that the piece is conductive in total.

@kevinjoe4388 3 жыл бұрын

This is what i needed. Where can i source the thin glass fiber sheet?

@andreschavarria1450 3 жыл бұрын

You can easily make that sheet yourself: take some peel ply, a thin glass fiber fabric, wet it with some epoxy resin, put another layer peel ply on top, press everything between even surfaces.

@kevinjoe4388 3 жыл бұрын

@@andreschavarria1450 Thanks🖒

@jinjiuyicarbonfiberteamsti652 3 жыл бұрын

Hi, we manufacture carbon fiber sheets, please check here: www.jinjiuyi.net/carbon-fiber-sheets/

@dejayrezme8617 5 жыл бұрын

Hmmm, beerings :) I had to look it up because I'm a non native speaker too, but it's bârˈĭng Thanks for the video, super interesting! Something I never thought about, you'd definitely wouldn't want your part to fail because of that.

@andreschavarria1450 5 жыл бұрын

Thanks for the comment. Next time ;)

@parrotraiser6541 3 жыл бұрын

What is the voltage generated there, and which direction does the current flow?

@andreschavarria1450 3 жыл бұрын

That depens on the metal paired with the carbon composite. Take, for example, aluminium, which is almost on the opposite end of the galvanic series compared to graphite (carbon). The voltage difference is over 1 volt, where graphite is losing electrons to the aluminium. If you take titanium, for exmaple, the voltage difference is much less and pairing these without insulation is less problematic.

@jamesharrison5004 2 жыл бұрын

Correct me if I'm wrong but isn't there a difference between conductivity and galvanic corrosion. For corrosion to occur you need a substrate like water present too.

@andreschavarria1450 2 жыл бұрын

Your're perfectly right. For galvanic corrosion to take place a current must flow, which means you need, for example, a liquid substrate rich in ions, but also that the two conducting materials have contact. Checking conductivity between them is the easiest way to show that they are not contacting, so that current cannot flow and galvanic corrosion cannot take place - irregardlessly of the presence of a liquid substrate.

@IkarimTheCreature 9 ай бұрын

@@andreschavarria1450 I have a question, if the part is submerged in say salt water that's conductive, wouldn't that short circuit the glass fiber barrier and cause galvanic corrosion?

@andreschavarria1450 9 ай бұрын

@@IkarimTheCreature No, it won't, because galvanic corrosion needs current to flow at the interface between metal and carbon fiber. You need salt water or other ionic solution to have galvanic corrion at all. But as long as carbon fibesr are not touching the metal, current cannot not flow, because you need to close the circuit. You can think of it like a usual battery. See en.wikipedia.org/wiki/Zinc%E2%80%93carbon_battery

@IkarimTheCreature 9 ай бұрын

@@andreschavarria1450 thank you, I had trouble wraping my head around this

@crashtestdummie67 5 жыл бұрын

Hello! I really like your lever design. For the ultimate in weight reduction you should check out plastic bearings. Like this: www.igus.com/product/390 and this: www.igus.com/product/93 The weight is nothing, you wont have galvanic corrosion, they are cheap and they work on carbon shafts, they last long and they tolerate rain. Does not use lube. What is your thought on this? I am designing a suspension system with swing arms and is only using plastic bearings. But its not built or tested yet... How did you make the flange for the roller bearings in the middle of lever?

@crashtestdummie67 5 жыл бұрын

I see this link so I get the picture about the flange..hortenmicrolight.wordpress.com/2019/01/12/engineering-lever-arms/

@hokiebama1187 2 ай бұрын

still need an electrolyte for corrosion to happen.

@andreschavarria1450 2 ай бұрын

yes, which is almost always available due to condensation. Big sailplane producers made the mistake to underestimate this and had really bad issues with galvanic corrosion.

@Bakanelli 6 ай бұрын

You failed to mention that galvanic corrosion will only occur is the parts are touching (or are connected via conductor) !AND! ARE SUBMERGED IN ELECTROLYTE! If the different metals are touching but not submerged in electrolyte, galvanic corrosion won’t occur!

@andreschavarria1450 6 ай бұрын

If you read the comments below, you'll see that we mention that an electrolyte is needed. Nevertheless, you're wrong when you think that it has to be submerged in it. It is sufficient when condensed water and some salts are available. That's the reason why some sailplane producers had problems with galvanic corrosion, though the airplanes are seldom submerged in electrolyte.