Metallographic Preparation Methods for Highly Porous Additively Manufactured Metals

When standard methods of metallographic preparation are performed on certain additively manufactured materials, results can misrepresent the fraction and size of microstructural features in some cases. This is most drastically observed when measuring the porosity volume fraction and size in highly porous metals, as smeared metal from standard preparation techniques can cover pores and mask the true degree of porosity. Furthermore, this smeared metal effect can be difficult to detect with standard light microscopy even at high magnification, making proper preparation essential to accurate test results. Metallographic preparation techniques for highly porous additively manufactured metals are presented, including comparisons between results using standard preparation methods and the modified methods presented in this paper.

Keywords: Metallography, preparation techniques, additive manufacturing, light microscopy, testing, porosity.