Evaluation of Sprayed Coatings by Electrical Method

Evaluation of adhesion properties has been tried by an electrical method. An electric resistance is measured to understand the way to evaluate adhesion between a low carbon steel substrate and sprayed coatings of Zn-Al alloy. The electrical load is changed during measurement. The electric resistance is changed during measurement of electric resistance, and some information may be useful for better understanding of the adhesion strength of the alloy. The electric responses give the information of contact area of the sprayed coatings and of qualitative state of porosity in the sprayed coatings. The electric resistance tends to decrease if the adhesive strength is large.