Hello
I have a two part question, maybe this forum can help with some of these issues (I am trying to gold plate a suite of different materials that will be in contact with high temperature solutions).

First, I want to gold plate over a nickel plating on a titanium substrate. The gold plated surface will be in contact with a high temperature solution, over a period of a couple of days to a week max. Can this be done? Is Nickel the best suited material to be sandwiched between Titanium and a gold plated surface?

Second, I want to gold plate onto a hastelloy C-type alloy (that gold surface will also contact a high temperature solution up to 300degC and max. one week time period). What type of plating(s) is/are best suited to be sandwiched between the hastelloy C substrate and the top gold plated layer so that the gold plated surface is stable and does not "peel off" or become otherwise detached?

Thanks for any advice in advance
Kono