Stripping NiCr-AG-NiCr Coating
Q. To strip NiCr-Ag-NiCr coating, I was preparing a solution @4% of Cerium Ammonium Nitrate (C.A.N.)and I added Citrajet @1% to be used as a wetting agent (surface inclined). The addition of Citrajet neutralized completely the effect of the C.A.N; which did not attack the NiCr layers. Can you give me some explanation and which Alconox product I have to use as wetting agent.
A. CAN is a very strong oxidizing agent. Organic functional groups with double bonds, alcohols, benzene rings and ethers are likely to be oxidized by CAN, thereby “neutralizing,” or depleting it, thereby rendering it less effective for stripping coatings. Most wetting agents have organic functional groups that will be oxidized by CAN, including Citrajet.
Electronics Cleaning – Kovar
Q. What is Kovar? What cleaner would be recommended to clean Kovar?
A. Kovar is made up of 29% nickel, 17% cobalt, .2% silicon, .3% manganese and 53.5% iron. Kovar is known for its low coefficient of thermal expansion. Kovar end uses are usually glass sealing in the electronics industry.
Etching with Citrajet?
Q. My system has the following materials in it: CPVC, stainless steel, cast iron and copper; should I expect an 8% Citrajet solution to etch any of these materials?
A. No etching will occur on CPVC, Stainless Steel, cast iron and copper from 8% Citrajet. Cast iron might rust in the rinse water, especially if you use hot rinse water. Use water below 120 deg F to rinse cast iron and then dry quickly by removing rather than evaporating water if possible. (remove with a solvent, forced air/gas, or wipe).
Cleaning Aged Aluminum
Q. How to clean weathered oxidized or aged aluminum with a dark grey buildup of oxides especial architectural aluminum or decorations on buildings.
A. We do not have a product suitable for this but we do have recommendations. Citranox and Citrajet are well suited to cleaning freshly manufactured aluminum items, but not aged and weathered aluminum items.
Electronics Cleaner – Circuit Boards w/ Alodine
A customer needed to clean an assembly of a printed circuit board which had been sweat soldered to an aluminum plate/heatsink/carrier. The company needed a cleaner that would not attack the Alodine coated aluminum backside or the gold pockets or solder reflowed surface of the circuit board.
Unfortunately, the current cleaner was slightly base ph 9+ and the water slightly alkaline as well coming in at a ph of 8.0. This, along with other factors, caused staining, darkening and spotty discoloration of the 6061 Alodine coated (chemical conversion coating) aluminum parts.
