Influence of sodium borate concentration on properties of anodic coatings obtained by micro arc oxidation on magnesium alloys

► Sodium borate decreases the electrical conductivity of an alkaline solution. ► Sodium borate can cause intensive spark discharge on sample surface during MAO. ► The boron content of anodic coatings is within the range of 0.84-5.10 at.%. ► The coatings formed in solutions containing sodium borate consist of Mg3B2O6.