Microstructural study of plasma sprayed hydroxyapatite coatings
Journal Title: Journal of Achievements in Materials and Manufacturing Engineering - Year 2017, Vol 2, Issue 83
Abstract
Purpose: The aim of this study is to present microstructure and mechanical properties of hydroxyapatite coatings sprayed by means novel plasma system with axially injection of powder. Design/methodology/approach: Coatings were deposited with Axial III plasma spraying system and examined by SEM, XRD and by a nanoindentation technique (Nanovea) with a Berkovitz indenter. Surface of coatings was analysed by means of a Talysurf CCI-Lite non-contact 3D profiler. Findings: This study shows the microstructure and mechanical properties of hydroxyapatite coatings (HA) obtained by plasma spraying from the powder with a cauliflower-like high porous structure consisting of nanograins with dimension below 100 nm. The cross-section of plasma sprayed HA coating reveals lamellar structure containing pores in the interior of the lamellae. Moreover, between lamellae, some microcracks were detected. Hardness and elastic modulus measured by nanoindentation were found to be around 0.085 and 6.82 GPa respectively, what was comparable with HA coatings sprayed by a modified cold spray system. Both XRD patterns are practically identical, so no new phases were created in hydroxyapatite coating in comparison with feedstock powder during the spray process. High values of a geometry of HA coating; maximum peak height, maximum pit height and maximum height confirmed significant roughening of a surface, which is a result of the interaction of melted powder grains with the surfaces during the plasma spraying. Research limitations/implications: Obtained properties of coatings will be the base for comparison with suspension plasma sprayed coatings. Practical implications: Hydroxyapatite coatings deposited by means novel plasma system are designated for spraying implants. Originality/value: Properties of hydroxyapatite coatings plasma sprayed with novel axially injection of powder.
Authors and Affiliations
S. Kowalski, R. Belka, W. Żórawski, M. Sztorc, A. Góral
Characterization of thermally oxidized titanium based coating
Purpose: Aim of the study is to improve the bioactivity of CoCr alloy upon covering the surface with titanium based coating.Design/methodology/approach: CoCr alloy was coated by cold spraying of powder mix...
The corrosion resistance of laser surface alloyed stainless steels
Purpose: of this paper was to examine the corrosion resistance of laser surface alloyed (LSA) stainless steels using electrochemical methods in 1M NaCl solution and 1M H2SO4 solution. The LSA conditions and alloying powd...
Microstructure and strengthening model of Al-3%Mg alloy in a heat treated state subjected to ECAP process
Purpose: The aim of this paper is to investigate the microstructure evolution of a heat treated Al-3%Mg aluminium alloy subjected to the ECAP (equal channel angular pressing process). Design/methodology/approach: Commerc...
Properties of titanium coating deposited using spheroidal powders by cold spraying
Purpose: TThe purpose of this study was to investigate the microstructure and the properties of the Ti coatings cold sprayed using spheroidal powder on the Al 7075 alloy. Design/methodology/approach: The Ni powder with i...
Substantiation of expedience of application of high-temperature utilization of used tires for liquefied methane production
Purpose: The purpose of this investigation is to substantiate by means of numerical simulation the expedience of high-temperature utilization of used tires with subsequent methanation of fuel gases and separation of mult...