No one could not surpass strength this steel. According to one of the hypotheses, the secret of ancient technology covered in microorganisms.
After forging the strip of steel buried in a swamp. It is inhabited by microorganisms able to "eat" iron.
Eating this element from swords, they increased the relative concentration other metals, responsible, as we remember for the uniqueness of the sword.
Besides, selective eating of iron atoms led to education "microsaws " at the edge of the blade, which also increases the advantages of a sword. This is why so usefull to know properties of bacteria, living around.