Using Atomic Force Microscopy to Evaluate Microstructure for Direct Metal Laser Melted Titanium

Additive Manufacturing (AM) is a relatively new technology that could potentially revolutionize industrial manufacturing. Currently, papers have studied the mechanical properties and microstructure of AM materials without the use of Atomic Force Microscopy (AFM). This paper utilizes AFM to analyze the Widmanstätten microstructure and porosity of Direct Metal Laser Melted (DMLM) titanium samples. The mechanical properties of the titanium samples were collected, and the samples exhibited favorable yield and tensile strengths, but suboptimal ductile properties. The DMLM titanium seemed to have an increase in yield and tensile strength while the ductility seemed to decrease as a result of the fast cooling rate utilized in the DMLM process. AFM was used when analyzing the Widmanstätten microstructure which had an average surface roughness of 142 nm and the pore depth of one sample was 3.3 μm. The substantial depth of the pores could potentially be related to the decrease in ductility and it could increase the potential of future premature fractures. AFM provided a lot of useful information for this study and could provide even more information within the metallurgical field when studying the microstructure and porosity of metals, especially for AM materials.