I appreciate your answers
Our products are made by subsuppliers - I do not know everything about the processes.
The surface is light grey after glassblasting
The cleaning is performed at 55 °C, 5 minutes, pH about 9,0, the cleaning bath is also supposed to give some corrosion protection...
I use glass blasted stainless steel (AISI 304) in the production.
Unfortunately it sometimes turns dark (instead of stay grey/silver).
After glass blasting the surface is cleaned (alkaline cleaning), the supplier claims it is passivated.
Does anybody know the mechanisme of this colour change...
