TY - JOUR
T1 - Production and Corrosion Resistance of Thermally Sprayed Fe-Based Amorphous Coatings from Mechanically Milled Feedstock Powders
AU - Koga, Guilherme Y.
AU - Jorge Junior, Alberto M.
AU - Roche, Virginie
AU - Nogueira, Ricardo P.
AU - Schulz, Robert
AU - Savoie, Sylvio
AU - Melle, Ana K.
AU - Loable, Carole
AU - Bolfarini, Claudemiro
AU - Kiminami, Claudio S.
AU - Botta, Walter J.
N1 - Funding Information:
This study was supported by FAPESP (thematic project, Grant Number 2013/05987-8). G.Y. Koga gratefully acknowledges the financial support of FAPESP (Grant Number 2017/09237-4). The Hydro Quebec Canada is gratefully acknowledged for its support to the production of the HVOF coatings. The authors thank Petrobras for the financial support.
Funding Information:
This study was supported by FAPESP (thematic project, Grant Number 2013/05987-8). G.Y. Koga gratefully acknowledges the financial support of FAPESP (Grant Number 2017/09237-4). The Hydro Quebec Canada is gratefully acknowledged for its support to the production of the HVOF coatings. The authors thank Petrobras for the financial support. Manuscript submitted December 14, 2017.
Publisher Copyright:
© 2018, The Minerals, Metals & Materials Society and ASM International.
PY - 2018/10/1
Y1 - 2018/10/1
N2 - Mechanically milled FeCrNbB feedstock powders from commercial precursors were used to produce amorphous coatings through two different industrial thermal-spraying techniques: high-velocity oxygen fuel (HVOF) and flame spraying. Microstructure, thermal behavior, and hardness of the coatings and their corrosion resistances in acidic and alkaline chloride-rich media were comparatively studied. HVOF process was effective to produce ~ 200-µm-thick highly amorphous coatings with hardness over than 700 HV0.3 and low porosity (~ 5 pct). Flame-sprayed ~ 220-µm-thick coatings were nanocrystalline, composed of α-Fe, Fe2B, FeNbB, and Fe2O3 phases and presented hardness of 564 HV0.3 and ~ 10 pct porosity. Electrochemical measurements indicated that HVOF coatings exhibit higher corrosion resistance than flame-sprayed ones thanks to the higher amorphous content and lower porosity resulting from the former processing route. Electrochemical impedance spectroscopy results demonstrated that amorphous HVOF Fe60Cr8Nb8B24 (at. pct) coatings are interesting to protect mild steels such as the API 5L X80 against corrosion in chloride-rich environments.
AB - Mechanically milled FeCrNbB feedstock powders from commercial precursors were used to produce amorphous coatings through two different industrial thermal-spraying techniques: high-velocity oxygen fuel (HVOF) and flame spraying. Microstructure, thermal behavior, and hardness of the coatings and their corrosion resistances in acidic and alkaline chloride-rich media were comparatively studied. HVOF process was effective to produce ~ 200-µm-thick highly amorphous coatings with hardness over than 700 HV0.3 and low porosity (~ 5 pct). Flame-sprayed ~ 220-µm-thick coatings were nanocrystalline, composed of α-Fe, Fe2B, FeNbB, and Fe2O3 phases and presented hardness of 564 HV0.3 and ~ 10 pct porosity. Electrochemical measurements indicated that HVOF coatings exhibit higher corrosion resistance than flame-sprayed ones thanks to the higher amorphous content and lower porosity resulting from the former processing route. Electrochemical impedance spectroscopy results demonstrated that amorphous HVOF Fe60Cr8Nb8B24 (at. pct) coatings are interesting to protect mild steels such as the API 5L X80 against corrosion in chloride-rich environments.
UR - http://www.scopus.com/inward/record.url?scp=85049588977&partnerID=8YFLogxK
U2 - 10.1007/s11661-018-4785-y
DO - 10.1007/s11661-018-4785-y
M3 - Article
AN - SCOPUS:85049588977
SN - 1073-5623
VL - 49
SP - 4860
EP - 4870
JO - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
JF - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
IS - 10
ER -