Title: Erosion-corrosion behaviour of Ni-based superalloy Superni-600 in the real service environment of the boiler

Authors: Pawan Kumar Sapra, Surendra Singh, Satya Prakash

Addresses: Department of Mechanical Engineering, Continental Institute of Engineering and Technology, Jalvehra, Fatehgarh Sahib-140406, Punjab, India. ' Department Metallurgical and Materials Engineering, Indian Institute of Technology, Roorkee, Uttarakhand, 247667, India. ' Department Metallurgical and Materials Engineering, Indian Institute of Technology, Roorkee, Uttarakhand, 247667, India

Abstract: Erosion-corrosion of boiler tubes remains an operational and economic constraint in power generation plants. Modifying process conditions, redesigning equipment, and selecting more corrosion-resistant materials are some of the methods the plants have used to combat corrosion. The erosion-corrosion behaviour of Ni-based superalloy Superni 600 was investigated by exposing it in the real environment of a boiler at 700 ± 10°C. The cyclic study was performed for 1,500 hours in the platen superheater zone of the coal-fired boiler. The investigation results may assist in proper selection of boiler tube materials in reducing erosion-corrosion in power generation facilities. The nature and chemical composition of the corrosion products have been characterised with respect to surface morphology, phase composition and element concentration using the combined techniques of X-ray diffractometry (XRD), scanning electron microscopy/energy dispersive analysis (SEM/EDX). The oxide scales consisted of NiO, Cr₂O₃, SiO₂, Al₂O₃ mainly.

Keywords: erosion-corrosion behaviour; superalloys; boilers; EDX analysis; nickel; boiler tubes; corrosion resistance; erosion.

DOI: 10.1504/IJMMP.2010.038153

International Journal of Microstructure and Materials Properties, 2010 Vol.5 No.6, pp.536 - 547

Published online: 19 Jan 2011 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article