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What chemical to degrease aluminum components
I am looking for a suitable solution for degreasing the components which will be treated to zinc yellow dichromate in one case, the other one is anodized to yellow color. the components are made of aluminumVedanarayanan
metal to rubber bonding - Salem, TamilNadu, India
They can be degreased in a vapor degreaser or with aluminum cleaner in an ultrasonic cleaner. However, preparation of aluminum for either zinc plating or anodizing involves many more steps than degreasing. After degreasing you usually need a non-etch alkaline aluminum cleaner, then probably an aluminum etchant, and then a desmutter before commencing anodizing or zincating for plating. Good luck.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
What the heck, I'll try to answer one here, I've been reading and enjoying these expert forums for around 3 hours now.
When I was an undergrad in chem, when we had an unusually tough grease or organic stain on glassware, we always used an acid bath (to ensure no metal contaminants were on the glass) then a base bath. The acid bath was simply 6 M HCl, and the base bath was Alcoholic KOH.
Turns out, Alcoholic KOH is one beauty of a degreaser. Probably wouldn't work for your application, though, it would probably etch the aluminum (although it shouldn't, I know that it etches glass...slowly).
If that didn't work, we went right up the scale to Aqua Regia, Peroxyl H2SO4, Chromic Acid, and as a method of last resort, HF. Don't even ATTEMPT any of these solutions. HF can kill very painfully and the rest can maim you so badly that you don't want to continue living (if you don't know EXACTLY what you are doing, and sometimes if you do).
Lots of recepies for Alcoholic KOH can be found, there is no proprietary mix. Actually, for the most part, it doesn't even matter if you use MeOH or EtOH.Dan Wigersma
- St. Joseph, Missouri
- Chennai, India