<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>The article presents the results of testing of Ni-Al alloy coatings with different chemical and phase composition, which might replace currently used electrolytic chromium coatings. Crust chromium coatings are suitable for reconditioning of machine parts because of their very good maintenance properties. However, due to toxicity of electrolytic chromium bath, their application tends to be restricted. Thermal flame and plasma spraying technologies were chosen for nickel aluminium coating application. Obtained coatings were distinguished by significant porosity of structure and surface roughness. The thickness of coatings ranged from 440 to 683 μm. Microhardness of coatings was not related to applied metal plating technology but to chemical and phase composition. The more aluminium content in coating the harder the coatings were. The hardness of coatings which resulted from NiAl phase was ca 250 HV 0.04. Flame spray coatings are distinguished by nearly 10 times higher corrosion current density compared comparatively with plasma spray coatings. The value of corrosion potential is influenced by structure and chemical composition of coatings. The more aluminium content caused the lower E<sub>corr</sub>.</p></abstract>

The article presents the results of testing of Ni-Al alloy coatings with different chemical and phase composition, which might replace currently used electrolytic chromium coatings. Crust chromium coatings are suitable for reconditioning of machine parts because of their very good maintenance properties. However, due to toxicity of electrolytic chromium bath, their application tends to be restricted. Thermal flame and plasma spraying technologies were chosen for nickel aluminium coating application. Obtained coatings were distinguished by significant porosity of structure and surface roughness. The thickness of coatings ranged from 440 to 683 μm. Microhardness of coatings was not related to applied metal plating technology but to chemical and phase composition. The more aluminium content in coating the harder the coatings were. The hardness of coatings which resulted from NiAl phase was ca 250 HV 0.04. Flame spray coatings are distinguished by nearly 10 times higher corrosion current density compared comparatively with plasma spray coatings. The value of corrosion potential is influenced by structure and chemical composition of coatings. The more aluminium content caused the lower Ecorr.

Properties of Thermal Spraying Ni-Al Alloy Coatings

Mechanical Faculty, Department of Marine Maintenance, Gdynia Maritime University

Advances in Materials Science

{"article-title":"Properties of Thermal Spraying Ni-Al Alloy Coatings"}

The article presents the results of testing of Ni-Al alloy coatings with different chemical and phase composition, which might replace currently used...

Properties of Thermal Spraying Ni-Al Alloy Coatings

Published Online: Jul 17, 2009

Page range: 30 - 40

DOI: https://doi.org/10.2478/v10077-009-0004-2

Keywords
thermal spraying, nickel-aluminium coating, corrosion, intermetallic coating

This content is open access.

Properties of Thermal Spraying Ni-Al Alloy Coatings

Published Online: Jul 17, 2009

Page range: 30 - 40

DOI: https://doi.org/10.2478/v10077-009-0004-2

Keywordsthermal spraying, nickel-aluminium coating, corrosion, intermetallic coating

This content is open access.

Keywords
thermal spraying, nickel-aluminium coating, corrosion, intermetallic coating