(b) Another very important factor for galvanic corrosion is the ratio of the area of two dissimilar materials joined together . If the ratio of area of more noble material and less noble material is 1:1 then the chance of galvanic corrosion is minimised despite having more potential difference between the materials . If the area of the more noble material ( cathode – say SS ) is less and the less noble material ( Anode – say steel ) is more then also the chance of galvanic corrosion is minimised. But if the area of Cathode ( SS )is more and area of Anode ( steel ) is less then there is maximum chance of galvanic corrosion. This is the reason why SS plates are not joined with MS bolts or screws ( SS cathode plate area is much higher than small Anode bolt or screw area ) to avoid galvanic corrosion.