Hardening of Steel Components by Microarc Oxidation Using an Aluminum Sublayer Obtained by Cold Gas-Dynamic Spraying

Механика машин, механизмов и материалов

Alexander I. Komarov¹  Georgiy G. Goranskiy² 

[1] Joint Institute of Mechanical Engineering of the NAS of Belarus;Science and Technology Park of BNTU “Polytechnic”;

关键词: cold gas-dynamic spraying;    microarc oxidation;    ceramic coating;    adhesion;    microhardness;    corundum;   

DOI  :  

来源: DOAJ

【 摘 要 】

The efficiency of creating oxide-ceramic coatings on the surface of steel products is demonstrated by the combination of preliminary cold gas-dynamic spraying of an aluminum sublayer and its subsequent microarc oxidation. The resulting gas-dynamic coatings are a composite material consisting of an aluminum matrix and inclusions of corundum particles (~15%), assimilated from the powder sprayed. Homogeneous with a low (1–6%) porosity base structure and evenly distributed corundum particles provide a high level of adhesion (up to 122 MPa), hardness (upto 1140 MPa) and viscosity (up to 46%) of coating. The ceramic coatings formed on an aluminum sublayer with a thickness of up to 180 μm are characterized by a homogeneous structure of the base layer. The phase composition of the surface layers of coatings is represented by γ-Al2O3, high-strength α-Al2O3 oxides and mullite, the content of which is 45%, 40%, 15%, respectively. With the deepening into the coating, a significant (up to 80%) increase in the content of Al2O3 is noted with a simultaneous decrease in the volume fraction of γ-Al2O3 and the absence of mullite. A consequence of this is a sufficiently high (up to 19 GPa) level of maximum hardness values in these coating layers, a reduction in the coefficient of friction to a value of 0.048 at the stage of steady wear with limited oil supply, and no wear of the ceramic coating under these test conditions.

【 授权许可】

Unknown