Mr.E.Hariharan , Ms.E.Jamuna
Strength of modified 9Cr–lMo steel, which is used in the normalized and tempered condition, increases with increase in solutionising temperature with a corresponding reduction in percentage elongation. Initially P91 steel (9Cr- 1Mo) plates were normalized and tempered, then microstructures determined by image analyzer and metallurgical microscope. Welding of P91 steel is done by using Shielded Metal Arc Welding (SMAW).Immediately after the completion of the welding post heating was carried out at 7300C for duration of 2hours. The microstructure performance in the welding zone of P91 steel, base metal and heat affected zone were examined by means of image analyzer and inverted metallurgical microscope. Thereafter hardness of throughout specimen determined using micro hardness tester. Then electro chemical polarization and behaviour of P91 steel has been investigated in acid and alkaline environment. Corrosion studies of P91 steel in concentrated acid as well as basic scarcely reported. Therefore corrosion behaviour of P91 steel of different concentrated of solution of dilute hydro chloric acid and dilute sulphuric acid used as corrosion environment. Finally, determination of corrosion rate and tafel plots drawn by electrochemical analyzer.