With the current trends to make a transition from permanent to temporary medical implants, the indispensable presence of metallic materials in medicinal applications has been extended to the research of biodegradable metallic materials. Taking the disadvantages of slow decomposition of Fe-based alloys into account, the addition of Mn and consequently alloys from the Fe-Mn system is considered one of the most promising for manufacturing and subsequent use in applications for medical purposes. In the creation and development of new alloys and products from the above binary system, which would show an increased degree of degradability, we have chosen a selective laser melting due to the creative advantages of additive manufacturing.
Through our research, we firstly demonstrated the differences between the use of mechanically mixed elemental metal powders and prefabricated alloy metal powders systematically. The rate of corrosion progression as well as the dissolution of products from the compared metal powders made by selective laser melting in different media can be assessed as entirely comparable.
With the ability of modifying the operating parameters (laser power and scanning speed), we created process maps at different levels of material characterization, which served us to determine the impact and optimize the parameters. It all led to the selection of the most favorable operating parameters to increase the reaction surface and consequently to a faster progress in corrosion. From the need to overlap the laser diameter and the hatch distance, we have derived a new equation to calculate the input energy density. For a more detailed analysis, and to determine the impact of process parameters, we have also compared the samples manufactured with the same input energy density but using different laser power and scanning speed combinations.
Despite the general inhibition of the corrosion rate with the addition of Ag, we have managed to produce a material with as much as 1775.22 μm /year with FeMnAg alloy and almost half the value of the generated porosity.