Efficiency of the Low-pressure Cold Plasma in the Cleaning of Steel Sheet for Subsequent Covering

This research was carried out a comparative analysis of cleaning of sheet steel, for use in forming processes impregnated with a mixture of SAE 40 oil and diesel by means of low-pressure cold plasma. The plasma discharge was generated by radio frequency energy using two types of gases, argon and oxygen. Cleaning of the surface was evaluated by measuring the contact angle with deionized water, diiodo methane and ethylene glycol, for the calculus of the surface free energy by means of the Fowkes theories and Wu and gas chromatography. The results show that the plasma cleaning is more effective when using a previous cleaning, in this case the immersion in solvent (CH
₃
-OH).