Effect of Trace Yttrium Oxide on the Microstructure and Properties of Porous Mg-Al Alloy

Abstract

Mg-based porous materials have broad application prospect in biomedical field.In order to improve the corrosion resistance of porous Mg-Al alloy in human body fluid，porous Mg-Al alloy was prepared by powder metallurgy，and Y2O3 with different contents (0，0.2%，0.4%，0.6%) was added to modify the Mg-Al alloy.The effects of Y2 O3 content on the porosity，pore morphology，microstructure，compressive strength and corrosion resistance of porous Mg-Al alloy in Hank's biomimetic solution were investigated by means of metallographic microscope，XRD，SEM，universal testing machine and electrochemical workstation.Results showed that the porosity of porous Mg-Al alloy prepared by powder metallurgy was about 39%，and the powder metallurgy method could accurately control the pore morphology and size of porous Mg-Al alloy.Moreover，porous Mg-Al alloy was mainly composed of Mg and the second phase Al12Mg17.The addition of Y2O3 could refine the grains of porous Mg-Al alloy，homogenize the grain size，distribute the second phase more evenly，and improve the compressive strength of porous Mg-Al alloy and its corrosion resistance in Hank's bionic solution.When the content of Y2O3 was 0.4%，the compressive strength of porous Mg-Al alloy was 46.4 MPa，and the corrosion rate in Hank's biomimetic solution was 0.887 44 mm/a.

Keywords

• porous mg-al alloy|y2o3|compressive strength|corrosion resistance|hank’s bionic solution