Hey guys/gals,
I did some fun testing, and decided you might enjoy the results. I posted some of this on another thread, but figured for the sake of discussion, I'd go ahead and put it here in a bit more detail.
I encountered some extreme corrosion a while back, and through much deductive reasoning, concluded that the damage was caused by electrolysis. I decided to replicate the corrosion with an accelerated time scale.
- I took a 1 gallon mason jar, filled it 3/4 of the way up with plain old tap water, and added approx 1 tablespoon of table salt. (I was aiming for extreme results
- I set up my power supply to run at 24VDC at a maximum of 2.75 Amps.
- I chose the same parts we were having issues with in the field, which were hydraulic pump parts.
- I suspended the parts so a small portion of the part was sticking out of the water. I did this by simply hanging the part from an aligator clip wire attached to the mouth of the jar with a vice grip making sure that the clip did not touch the water.
- I hooked the clips to the power supply + and -. For the first test I used a steel flat bar hooked to the negative side, and a brass wear plate to the positive side and let them sit with voltage applied for 6 hours, checking once an hour.
- The brass wear plate was initially 0.101" thick, with a polished finish.
Through the wonder of electrolysis, 6 hours later when I pulled the wear plate from the salt water this is what it looked like:
The final thickness was only 0.061, 6 hours later.
As you can see I was able to completely devistate this part in less than a single working shift.
During this test, the steel bar that was used as the negative electrode suffered no damage to speak of.
What I did find interesting was this piece:
The picture above shows a part that was simply dropped to the bottom of the mason jar with no direct electrical connection to the two parts which had direct power applied. This ambient part also suffered elevated corrosion simply by sharing the fluid with the two parts which were being "electrified". In theory, this part had no electrical current flowing through it.
The second test: I wanted to see just how much damage I could do in one hour using the exact same process. The picture below was another identical hydraulic piston:
This test was done using two identical new pistons as the anode and cathode. You can easily see where the waterline was during the test.
This corrosion was obtained in 1 hour, yes 1 hour.
The piston above was connected to the positive lead. Although the negative lead did corrode substantially, it was to a much lesser degree than the one pictured above.
This type of corrosion can occur any time you have a (even slightly, such as tap water) conductive fluid, and a DC voltage source.
I have seen this type of damage wipe out complete systems worth millions of dollars. The problem is, it's hard to pinpoint the source of the voltage leak, and sometimes even harder to diagnose in the first place. All it takes is one leaking solenoid on a machine leaking 0.7VDC or more to wipe out the entire system.
Just something to keep in the back of your mind in case you run across it in the field at some point. Many people that I have talked to about this problem had no idea that it even existed, and had been simply replacing parts on a regular basis with no idea why the parts would need replaced so frequently.
Electrolysis is a silent killer in some situations.
Be aware, and you might just save your company millions of dollars worth of replacement parts.
Electrolysis Corrosion (NOT FOR HHO!) 
Re: Electrolysis Corrosion (NOT FOR HHO!)
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