Flaking Zinc Plate

Q: We have a customer who returned zinc-nickel plated parts to us which we processed in 2005 and have traveled to Asia. The plating is flaking from the parts. They are returning 3,000 pieces out of 40,000 pieces that were plated in 2005. Do we have an argument as to what effects the environment and storage could do to these parts? Our company is paying for this rework, yet I don’t think we are responsible for redoing the flaking parts. Do you have any thoughts on this? S.I.

 

A: My immediate answer is that after shipment to Asia and storage for three years, your customer has no solid grounds for asking for a “redo.” Your company had no control on the storage conditions and from what I gather, how the parts were stored. In three years of storage, particularly in a humid environment, you certainly could expect damage to the zinc plate.

That said, in order to give you a better answer to your question additional information is needed. What is the base material? I assume it is a steel of some type, but I have learned over the years that one should never make any assumptions about this. What type of zinc plating was used? Cyanide, alkaline non-cyanide or acid zinc? The plating process can make a difference.
You mentioned in your e-mail that 3,000 out of a batch of 40,000 pieces were returned to you. Do you have any way of determining whether 3,000 parts came from one lot or from multiple lots?

Last but not least, it would be helpful to find out from your customer how the parts were stored.

Storage of parts for three years seems like a very long time, particularly in this day and age when companies do not like to accumulate inventory.