Thermally sprayed coatings can prevent corrosion in biomass boilers

Davide Fantozzi

A deep understanding of the corrosion behaviour of protective coating enables the application of better corrosion control strategy. This allows more efficient power generation from combustion of green fuels, says Davide Fantozzi in his doctoral dissertation. In his work he studied how different coating materials respond to aggressive high temperature alkali chloride corrosion conditions such as those present in biomass boilers.

Power generation by combustion of carbon neutral fuels such as biomass is one of the many actions necessary to increase the sustainability of the energy sector and curb climate change emissions. Unfortunately, one of the many challenges in biomass combustion is the corrosivity of the biomass’ ashes for the hottest parts of the boiler. Thermal spray coatings can reduce corrosion by acting as protective layers.

“Even the same feedstock material, if deposited with different thermal spray techniques, will result in coatings with different microstructural features and therefore performance. It’s important to understand how these features affect the material’s properties,” explains Davide Fantozzi.

Fantozzi used various analytical and test methods both in laboratory and in actual boiler environment to describe the corrosion mechanism as it occurs in the complex microstructure of thermally sprayed coatings. He was able to determine important environment conditions at which such coatings can be applied safely.

“It was exciting to experiment with a combination of traditional and unconventional methods to study the corrosion behaviour of my coatings. Seeing them work and generate new data about my materials was extremely rewarding,” says Davide Fantozzi.

Davide Fantozzi has worked at Valmet Technologies from 2018 to 2021, and has now relocated back to his hometown Modena, Italy, to work as development engineer for Tetra Pak.

The doctoral dissertation of MSc (Tech) Davide Fantozzi in the field of materials engineering titled Chlorine-induced High Temperature Corrosion of Thermally Sprayed Coatings will be publicly examined in the Faculty of Engineering and Natural Sciences at Tampere University on Friday 15th of October 2021 in the auditorium K1702 of the Konetalo building (Korkeakoulunkatu 6, Tampere). The Opponents will be Dr. Esmaeil Sadeghi from the University of Waterloo and Dr. Keijo Salmenoja from Andritz Oy. The Custos will be Prof. Petri Vuoristo from the Faculty of Engineering and Natural Sciences.

Link to remote connection:

The dissertation is available online at

Photo: Mika Kanerva