2 research outputs found
Površinska obrada laserom Mg-Al-Zn legura
In this paper the structure and properties investigations results of the cast
magnesium alloys in the as cast state, after heat treatment and laser surface
treatment are presented. The aim of this work was to improve the surface
layer properties of the Mg-Al-Zn cast magnesium alloys by melting and
feeding of TiC, VC, WC, SiC, NbC and Al2O3 particles onto the surface.
Laser processing was carried out using high diode power laser (HDPL).
A series of experiments was carried out with varying scan rates and laser
power. The resulting surface layers were examined using metallographic
optical microscopy, scanning electron microscopy, X-ray diffraction,
microhardness measurements and corrosion resistance tests. Mg-Al-Zn
alloys after laser treatment are characterized by two zones: alloyed zone
(AZ) and heat affected zone (HAZ) with different thickness and shape
depending on laser power and ceramic powder used. Alloyed zone is
composed mostly of dendrites with the Mg17Al12 lamellar eutectic and Mg
in the interdendritic areas. The increase of microhardness from about 50
HV0,1 to about 200 HV0,1 in alloyed zone were observed.U ovom radu prezentirana je struktura i mehanička svojstva ljevačke
magnezijske legure u ljevačkom stanju, nakon toplinske obrade i obrade
površine laserom. Cilj ovog rada je unaprijediti svojstva površinskog
sloja Mg-Al-Zn ljevačke magnezijske legure taljenjem i dodavanjem
čestica TiC, VC, WC, SiC, NbC i Al2O3 na površinu. Obrada laserom
izvodila se laserom visoke snage na diodi (HDPL). Serija eksperimenata
izvodila se varirajući brzinu skeniranja i snagu lasera. Rezultirajući sloj na
površini ispitivalo se metalografskim svjetlosnim mikroskopom, scanning
elektronskim mikroskopom, difrakcijom x-zrakama, mjerenjem tvrdoće i
mikrotvrdoće i testovima korozijske otpornosti. Poboljšanje proizvodne
tehnike i kemijskog sastava kao i metoda toplinske obrade dovode do
razvoja projektiranja materijala za optimalna fizikalna i mehanička svojstva
novorazvijenih legura