Mumbai, Feb 5 (PTI) The Indian Institute of Technology Bombay on Wednesday said its researchers have found a new technique that can measure the rate of degradation of coatings on iron, which could be useful for the steel industry.
By combining “hydrogen permeation-based potentiometry (HPP) and electrochemical impedance spectroscopy (EIS)”, the researchers efficiently measured the coating degradation rates on the industrially relevant metal, IIT Bombay said in a statement.
Metals often have a layer of protective organic coating, like the paint on cars, but they corrode with time, the premier institute said.
The efficiency of organic coatings deteriorates with time, eventually damaging the metal as they have pores and defects that allow water and oxygen to reach the underlying metal surface over time and corrode it.
The IIT Bombay researchers combined two electrochemical techniques, HPP with EIS, which allowed them to quantify the degradation rates at the interface between the organic coating and the metal, the statement said.
While HPP gives a direct measure of hydrogen permeation, EIS provides insights into how hydrogen permeation corrodes the coated metal.
“HPP-EIS can be used to monitor how quickly the organic coating will give way for the iron to rust, and that the method would be of interest not only to the steel industry but will also be useful in the field of fuel cells and sensors,” said Prof Vijayshankar Dandapani of the Department of Metallurgical Engineering and Materials Science at IIT Bombay.
HPP-EIS is cost-effective because it requires only two potentiostats, simple electronic devices that control and measure the voltage between two electrodes, said the statement.
“With hydrogen blending becoming increasingly popular to reduce emissions from natural gas, one can also apply the HPP-EIS technique to determine how quickly the coat of paint on a natural gas pipeline, where hydrogen is blended with natural gas, degrades,” Prof Dandapani added. PTI SM NR