Wire Yttria coating electrophoresis
Re: Wire Yttria coating electrophoresis
How much did the Nyacol yttria colloid cost you?
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- Real name: Silviu Tamasdan
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Re: Wire Yttria coating electrophoresis
I see an unanswered question in the OP that I may field.
I have used surfactants in electrolysis before, and in one case it was precisely for this reason (prevent gas bubble adhesion to avoid pitting).
It was a different application though so take this with a grain of salt.
I used Triton X-100, a nonionic surfactant, at 0.5% concentration. It gave reasonable results. The application was coating of a graphite anode with a layer of lead dioxide. The electrolysis conditions were vastly different (DC 4V, about 800mA for ~20min). The Triton degrades slowly over these conditions so its surfactant properties decrease over time but it should be good enough for runs of up to 1h. I don't know how it would fare under your conditions though.
Another method that I used to deal with bubbles in this particular system was centrifugal force. Essentially the piece to be coated is spun during electrolysis by a small electric motor. I used a 6V 20000rpm motor that I undervolted to 1.5V; this combined with the inertia of the piece+connecting shaft and the friction with the electrolyte resulted in a rotation speed of about 300rpm. That is enough to knock off bubbles as they form. Caution if you use surfactant at the same time as it can lead to a significant amount of foaming.
(edit) Here's a short video that I made during that process.
https://www.dropbox.com/s/lpuqob9fl9ruj ... t.mp4?dl=0
I have used surfactants in electrolysis before, and in one case it was precisely for this reason (prevent gas bubble adhesion to avoid pitting).
It was a different application though so take this with a grain of salt.
I used Triton X-100, a nonionic surfactant, at 0.5% concentration. It gave reasonable results. The application was coating of a graphite anode with a layer of lead dioxide. The electrolysis conditions were vastly different (DC 4V, about 800mA for ~20min). The Triton degrades slowly over these conditions so its surfactant properties decrease over time but it should be good enough for runs of up to 1h. I don't know how it would fare under your conditions though.
Another method that I used to deal with bubbles in this particular system was centrifugal force. Essentially the piece to be coated is spun during electrolysis by a small electric motor. I used a 6V 20000rpm motor that I undervolted to 1.5V; this combined with the inertia of the piece+connecting shaft and the friction with the electrolyte resulted in a rotation speed of about 300rpm. That is enough to knock off bubbles as they form. Caution if you use surfactant at the same time as it can lead to a significant amount of foaming.
(edit) Here's a short video that I made during that process.
https://www.dropbox.com/s/lpuqob9fl9ruj ... t.mp4?dl=0
There _is_ madness to my method.
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Re: Wire Yttria coating electrophoresis
Ian,
I ordered a sample of the yttria colloid.
It was for free.
I ordered a sample of the yttria colloid.
It was for free.