Hard Nickel Plate

Question:

We plate components with nickel using a nickel sulfamate bath. Besides nickel sulfamate, the bath contains magnesium chloride, boric acid and an antipitting agent. The problem we face is that the plate is too hard and brittle. What do you suggest? M.S.

Answer:

Your sulfamate nickel bath is in need of some “health management.” First of all, I have not heard of many people using magnesium chloride as their source of chloride ions. Replace the magnesium chloride with nickel chloride or, better yet, nickel bromide. Your bath also needs an activated carbon treatment. This will remove organics from the bath that build up over time. These “trash” organics can cause brittleness. Last, but not least, you should “dummy” your bath on a regular scheduled basis. A current density of 4–6 asf is recommended.

Please remember that your plating bath is a mixture of different components, and each of these components must be monitored on a regular basis. In my book, the less often you test and monitor your plating, the more likely you are to have problems.