Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: metal matrix composite coatings

Sortuj według:

Ogranicz wyniki do:

Investigations on the Microstructure and Corrosion Performance of Different WC-Based Cermet Coatings Deposited by High Velocity Oxy Fuel Process onto Magnesium Alloy Substrate

Jonda Ewa, Łatka Leszek, Maciej Artur, Khozhanov Aleksandr

Advances in Science and Technology. Research Journal

2023

Vol. 17, no 2

25--35

In the field of surface engineering, thermal spraying is very wide adopted in many branches of the industry. The main reasons of such situation are its flexibility as well as cost effectiveness. Among others, High Velocity Oxy Fuel (HVOF) technique is dedicated for spraying hardmetal and cermet coatings, especially for wear- and corrosion resistance. Such type of coating could be a promising candidate as protective layer for magnesium alloys elements. These materials need a strong improvement in the corrosion protection as well as on the field of wear resistance in order to be widely used in the industry. In this work, different WC-based coatings, namely: (i) WC-Co, (ii) WC-Co-Cr and (iii) WC-Cr3C2-Ni manufactured by HVOF spraying, were investigated. The form of all feedstock materials was agglomerated and sintered powder. All coatings were sprayed with the same technological parameters, especially spray distance which was equal to 400 mm on the AZ91 magnesium alloy substrate. The main aim of the studies was to investigate the influence of the powder material on the corrosion resistance of obtained coatings. The manufactured coatings were examined in terms of its microstructure, using scanning electron microscope (SEM) and corrosion performance, which was assessed in the electrochemical corrosion investigations in 3.5% NaCl solution by Tafel method. The study showed that the corrosion resistance increasing in such order: AZ91 < WC-Cr3C2-Ni < WC-Co < WC-Co-Cr. It should be stressed that WC-Cr3C2-Ni coating exhibits very low corrosion performance, which could be effected by relatively high porosity (c.a. 3 vol.%) and because of that the more complex composition promotes creation of many corrosion cells.

Finishing of the metal matrix composite coatings applied to regenerated parts of ship machinery

Dyl T.

Journal of Polish CIMAC

2012

Vol. 7, no 2

23-30

Most elements of ship machinery parts are regenerated during the cruise ship. Engineer often regenerates cylindrical outer surfaces (for example torque pump shaft neck). The welding technology of applying alloy and composite coatings is very common. The technology of infrasound thermal spraying of metal matrix composite coatings was presented. It is a simple technology and a very useful one in ship machinery regeneration during the cruise craft (e.g. internal combustion engines, torque pumps, separators). The metal matrix composite coatings must undergo finishing due to high surface roughness after application. The most popular is machining (e.g. turning or grinding). The authors also propose the application of finishing through turning. The paper should influence of the type of inserts on the geometric structure of the alloy Ni-5%Al and composite Ni-5%Al-15%Al2O3 coatings. Nickel - aluminium matrix composite coatings on were sprayed with a torch Casto-Dyn 8000 a steel substrate, and then turned lengthwise. In order to determine the optimum geometry of indexing, it is now synonymous with the selection of the optimum shape and dimensions of the insert and an appropriate holder. The insert was used in different shapes and geometries: square, triangular, trigon, made tungsten carbide and cubic boron nitride (CBN).