Anisotropic properties of additively manufactured components. Are they there?

Abstract

In this project we have focused on studying the properties of a product manufactured by a coating technique known as Cold Gas Spray. This technique is differentiated from the others by the fact that it deposits the material in its solid form using kinetic energy to deform plastically the particles which lead to obtain a deposition. Since this technique is principally used in coatings, it results of high interest to prepare and characterize a component by this method with a significant volume in order to know the capabilities of this technique as an Additive Manufacturing process and to know the generation of anisotropic properties in the component. First of all, it has been manufactured a high volume deposit from which it has been obtained two sample types: parallel (XZ) and perpendicular (XY) to spray direction. Afterwards, it has been analyzed the microstructure and porosity of both planes, as well as their corrosion resistance by using a Potentiodinamic Polarization. It has been also studied the mechanical properties of X, Y and Z directions via tensile test, and microhardness of XZ and XY planes with Vickers method. It has been proved in all the performed tests that there is a clear anisotropy between XY and XZ planes, as well as between Z direction and X and Y directions. XZ plane has been the one that presented higher levels of porosity, lower corrosion and stress resistance and lower microhardness. That is due to its lamellar microstructure, which indicates low compaction and cohesion between layers in the sample. Finally, samples have been thermally treated and it has been shown a considerable improvement in their properties, since they almost lose their anisotropic properties. However, they did not reach 316L Stainless Steel manufactured in a conventional manner