Aluminium nipple broken. Is this due to galvanic corrosion?

Hi all,

Thanks in advance. Just wanting an opinion. I had an aluminium nipple fail on my wheel. The wheel set is only two years old. I do live close to the seaside.

However, to also factor in, I did have a slight fall a week before the spoke nipple failed on me so not sure if that weakened that area.

In terms of the actual failure, it occurred under fairly heavy breaking whilst I was descending (approximately 8 to 9% gradient).

I’ve removed the wheel and rim tape (I run tubeless), and I didn’t really find any evidence of moisture inside the rim. The other nipples actually look okay as well.

After doing a bit of research, I’ve obviously become a bit concerned regarding the possibility of corrosion of the aluminium nipples and that all the other nipples might fail and I certainly don’t want to risk it again. So I’m wondering if I should get all the nipples changed out to brass nipples (in hindsight probably what I should’ve had in the first place!), or if this was just perhaps stress following the fall that I had the week previously.

Not too sure if there truly is any way of knowing/testing.

For what it’s worth all the other nipples look fine with no real evidence of corrosion that I can see superficially anyway. I’ve uploaded photos of the other nipples for what it’s worth as well as the broken nipple that I retrieved from inside the rim and also the thread of the spoke where the nipple broke.

Thanks for your opinions. If people say galvanic corrosion, then looks like I need to get all the aluminium nipples replaced. If people think that it looks absolutely fine, then I’ll just replace this one.