Metal finishing Q&As since 1989

-----

Electrolytic plating of aluminum tube - inner surface modified?

If a 0.250" OD x 0.150" ID x 2" long Type 1100 aluminum tube is plated with electrolytic nickel, ~0.0005" thick:

1. Approximately how far into the tube from the ends will plating on the ID extend?

2. Will there be any zincate or other modification of the aluminum surface on the ID near the center of the tube?

Grant Kiehne
manufacturing - Bloomfiield, Connecticut, USA
2004

Typical plate without an internal anode is 1 ID diameter deep with no plate by 2XID dia deep from each end.

James Watts
- Navarre, Florida
2004

---

Follow-up question:

Will the electrolytic nickel plating be well-adhered on the I.D.? In other words, if adhesion is driven by electric field, might there be lower/poor adhesion on the I.D.?

Grant Kiehne
manufacturing - Bloomfield, Connecticut, USA
2004

---

Typically , NO. You have an ID slightly more than 1/8 inch which will normally retain some of the last chemical or rinse as it goes into the next tank. (osmosis) This is going to require special procedures to flush each chemical and rinse into the tube. It is going to require superior agitation during plating, probably air, possibly pumped.

Since this is aluminum, it is going to make it difficult to get a great zincate which is the heart of adhesion for aluminum. Your tube is 2 inches long and you will have plate the ID about 1/4 inch from both ends. Is this really what you are looking for?

James Watts
- Navarre, Florida
2004