gold plating in saltwater

[mosley401]

thread321-126998

I'm working on a project developing amperometric water sensors in a saltwater envirnment. The cathode material I'm using now is gold-plated copper wire. I'm looking for information on gold-plating resistance to saltwater. I had been using solid gold for the cathode but due to cost changed to gold-plating. Some input from customers have expressed concerns over the durability of gold-plating in saltwater. Anyone have any knowledge on this?

 

[sphinxios]

i was just wondering about when you said cost of gold was an issue to your sensor, why can't you use some sort of inner material like carbon fiber or glassfiber and just use a thinner tube of gold outisde of the composite, carbon fiber conducts electricity and glass fiber doesnt, wether that would have anything to do with the sesnsors capabilities itself, my guess that there are other materials you could use intead of those on other that comes to mind is ceramics, could be an option too but is very brittle since i dont know if that sensor is under any mechanical stresses.

regards

 

[cloa]

The durability of the gold-plating would depend on the quality of plating and the conditions in the sea water basically abrasion by suspended particles and velocity of the water. There would be no simple answer but corrosion issues until a little of the gold plating failed or it was not completely coating in the first place. Then its considerable cathode to anode ratio with considerable galvanic difference 0.35V and copper will probably corrode and force off more gold.