NOTE 1. This chrat of weld meatl gives a rough idea of which weld metal is more cathodic to other . The chart has been prepared by my guesswork - taking similarity of composition of some of weld metals with some of base metals
and considering the composition of some of the welding alloys - for example for M66F , the weld contains high silver
( more cathodic in base metal list ) and high cadmium and other elements( which are more anodic in base metal list )
- so I have considered M66F in the midway of the list. This weld metal chart is not made by any real experimentation.