Corrosion behaviour of WE43 magnesium alloy printed using selective laser melting in simulation body fluid solution

journal article in Web of Science

en

Compared to other magnesium alloys, the WE43 alloy is better able to resist corrosion thanks to its unique chemical composition, it decomposes harmlessly in the human body and its mechanical properties make it a suitable candidate for a new generation of biodegradable bone implants. The present study deals with the relative density, microstructure, and corrosion resistance of the WE43 material produced using selective laser melting. For these purposes, thin-walled and volumetric samples were produced using various combinations of laser settings, specifically laser power in the range of 125-225 W and laser scan speed in the range of 500-700 mm/s. The width of thin-walled samples served as a basis for setting the hatch distance of the weld tracks in volumetric samples. Porosity analysis revealed that the highest relative density achieved among volumetric samples was up to 99.5% and the Mg vapours generated during the printing process were reduced. The corrosion rates for different surface quality in Hanks' Balanced Salt Solution were observed. The grinded batches (grit 4000, 500, and 120) of samples achieved the corrosion rate 2.11 mm.year(-1) for SiC4000, 4.48 mm.year(-1) for SiC500, and 5.12 mmyear(-1) for SiC120. Corrosion rate of as-build samples was established on 7.04 mm.year(-1), which was worse by an order of magnitude in comparison of extrude material.

Compared to other magnesium alloys, the WE43 alloy is better able to resist corrosion thanks to its unique chemical composition, it decomposes harmlessly in the human body and its mechanical properties make it a suitable candidate for a new generation of biodegradable bone implants. The present study deals with the relative density, microstructure, and corrosion resistance of the WE43 material produced using selective laser melting. For these purposes, thin-walled and volumetric samples were produced using various combinations of laser settings, specifically laser power in the range of 125-225 W and laser scan speed in the range of 500-700 mm/s. The width of thin-walled samples served as a basis for setting the hatch distance of the weld tracks in volumetric samples. Porosity analysis revealed that the highest relative density achieved among volumetric samples was up to 99.5% and the Mg vapours generated during the printing process were reduced. The corrosion rates for different surface quality in Hanks' Balanced Salt Solution were observed. The grinded batches (grit 4000, 500, and 120) of samples achieved the corrosion rate 2.11 mm.year(-1) for SiC4000, 4.48 mm.year(-1) for SiC500, and 5.12 mmyear(-1) for SiC120. Corrosion rate of as-build samples was established on 7.04 mm.year(-1), which was worse by an order of magnitude in comparison of extrude material.

Mg-alloy; WE43; Additive manufacturing; Corrosion rate; Microstructure; SLM

01.09.2021

ELSEVIER SCI LTD

OXFORD

1526-6125

69

1

556–566

11