Question

As the Iron Pillar was made up of iron but it has no rust why ts is the Iron Pillar of by wch Ashok build

Answer 1

The composition of Iron Pillar is mainly of iron but it is an alloy i.e. mixture of elements. Also, I found it was rusted, when I visited the place 2 years back from now.

Answer 2

because he had developed scienyific nethod of preventing corrison.
The pillar was manufactured by the forge welding of pieces of wrought iron. In a report published in the journal Current Science, R. Balasubramaniam of the IIT Kanpur explains how the pillar's resistance to corrosion is due to a passive protective film at the iron-rustinterface.