<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">Degradation examinations of outer surface of low-emission steam boiler evaporator tubes are presented in the paper. Metallographic evaluation of scale morphology, its micro sites chemical composition analysis and distribution of elements on cross sections have been performed. Water-wall tubes were exposed in steam boiler for up to two years period. Common tubes made of 16Mo3 steel suffered sulfide and molten salts corrosions. Thermal sprayed tubes with the single layer of 70%Ni 30%Cr alloy show better corrosion resistance, but become also susceptible to sulfide corrosion due to presence of internal voids and cracks. Double layer Al2O3/Ni-30Cr coatings withstand corrosion attack for more than one year operation, then failed due to internal heterogeneity and cracks generation.</abstract>

Degradation examinations of outer surface of low-emission steam boiler evaporator tubes are presented in the paper. Metallographic evaluation of scale morphology, its micro sites chemical composition analysis and distribution of elements on cross sections have been performed. Water-wall tubes were exposed in steam boiler for up to two years period. Common tubes made of 16Mo3 steel suffered sulfide and molten salts corrosions. Thermal sprayed tubes with the single layer of 70%Ni 30%Cr alloy show better corrosion resistance, but become also susceptible to sulfide corrosion due to presence of internal voids and cracks. Double layer Al2O3/Ni-30Cr coatings withstand corrosion attack for more than one year operation, then failed due to internal heterogeneity and cracks generation.

Assessment of Evaporator Tubes Corrosion in Low-Emission Steam Boilers

Department of Materials Technology and Welding, Gdansk University of Technology, 11/12 Narutowicza, 80-952 Gdansk, Poland

Institute of Engineering Materials and Biomaterials, Silesian University of Technology, 18A Konarskiego, 44-100 Gliwice, Poland

Department of Materials Science and Engineering, Gdansk University of Technology, 11/12 Narutowicza, 80-952 Gdansk, Poland

Advances in Materials Science

{"article-title":"Assessment of Evaporator Tubes Corrosion in Low-Emission Steam Boilers"}

Degradation examinations of outer surface of low-emission steam boiler evaporator tubes are presented in the paper. Metallographic evaluation of scale...

Assessment of Evaporator Tubes Corrosion in Low-Emission Steam Boilers

Published Online: Feb 07, 2009

Page range: 14 - 21

DOI: https://doi.org/10.2478/v10077-008-0046-x

Keywords
low-emission steam boiler, evaporator tubes, sulfide corrosion, thermal sprayed coatings

This content is open access.

Assessment of Evaporator Tubes Corrosion in Low-Emission Steam Boilers

Published Online: Feb 07, 2009

Page range: 14 - 21

DOI: https://doi.org/10.2478/v10077-008-0046-x

Keywordslow-emission steam boiler, evaporator tubes, sulfide corrosion, thermal sprayed coatings

This content is open access.

Keywords
low-emission steam boiler, evaporator tubes, sulfide corrosion, thermal sprayed coatings