Mechanical Cleaning Effectiveness
Q. We are coating nuts and fasteners with nickel alloys for corrosion resistance. We currently do mechanical cleaning before electrochemical cleaning but would like to eliminate this mechanical cleaning, as the system is not efficient. Could you give us information on a new process? —J.H.
A. It is not clear from your question why your mechanical cleaning process is inefficient, however, I would venture to guess that since you are performing an electrochemical cleaning process, the mechanical cleaning is not being done to remove oxides or scale. If you are attempting to degrease your parts, a mechanical cleaning process would not be effective. A chemical cleaning process such as a solvent or aqueous detergent would be advisable prior to entering the electrocleaning process. Since the electrocleaning is also an aqueous process, an aqueous pre-cleaning followed by thorough rinsing would be significantly more efficient than the mechanical cleaning process.
The processes, chemicals and equipment, plus control and troubleshooting.
The German Association of the Automotive Industry’s VDA Volume 19 is the first comprehensive standardization document for characterizing the cleanliness of products within the automotive industry’s quality chain.
Better adhesion, enhanced corrosion and blister resistance, and reduced coating-part interactions make pretreatment a must.