Back a few days ago we were caught up on the topic of rust. Bhimasena commented that there is a very interesting iron pillar in Delhi. I put that on the list of potential things to blog about.
Unfortunately, most of the treatments of the subject I could come up with revolved around the phallic aspects of the whole thing, and the Ideal Me that fronts in this blog couldn’t get control of Real Me’s desire to devolve into earthy humor.
Here is a more suitable presentation of the idea:
Indians Develop New Iron Using Ancient Technology:
Indian metallurgists have developed a type of corrosion-resistant iron that construction engineers would love. And vital clues for it came for Delhi’s famous Iron Pillar that has been standing tall for over 1,600 years.Developed by Ramamurthy Balasubramaniam and his former student Gadadhar Sahoo of the Indian Institute of Technology (IIT) in Kanpur, the iron contains phosphorus and shows remarkable resistance to corrosion, especially in concrete.
‘This is a significant first step in the possible commercial (large-scale) use of these irons,’ Balasubramaniam, better known as Bala, told IANS.
Most steels today contain small amounts of carbon and manganese. Modern steel makers avoid phosphorus because its segregation to grain boundaries makes the steel brittle.
But the IIT team successfully produced ductile phosphoric irons by driving the phosphorus away from grain boundaries through clever alloy design and novel heat treatment.
Ironically, Bala’s material is not new. It was being made by Indian ironsmiths centuries ago. Bala says he got the clue for developing this material from the six-tonne seven-metre tall Delhi Iron Pillar – a major tourist attraction in the Qutb Minar complex — that has been standing for centuries in the harsh weather of the capital without any corrosion…
‘As a metallurgist, I was intrigued,’ Bala told IANS. And his passionate quest to unravel the mystery that began in 1990s has now culminated in phosphoric irons.
The test samples developed by the IIT team remained fresh after three months of being immersed in solution, simulating the corrosive concrete environment, whereas the best commercially available steels got rusted. In another experiment, they embedded the samples in concrete to simulate actual conditions and obtained similar results…
‘The recent bridge collapse in Minneapolis has added new urgency,’ Welsch said in a congratulatory message to Bala. Seven people died when the bridge across the Mississippi river collapsed Aug 2, 2007…
Further studies and analysing rust from the pillar showed that phosphorus catalysed the formation of a protective passive film on the surface of the pillar that acted as a barrier between the metal and rust…
‘Certainly, we are not claiming that this is the end of our studies,’ admits Bala. ‘We have shown the usefulness of phosphoric irons for concrete reinforcement applications. Now it has to be taken up by more researchers for greater understanding.’Bala thanks his forefathers for the success. ‘I am of the firm belief that ancient Indian metallurgists had the empirical knowledge that high phosphorus content ores resulted in corrosion-resistant iron. They did not create this material by accident.’
