One of the challenges of 3D printing is getting repeatable results, such as good mechanical properties and the same microstructure, using different construction directions. A lot of research has been published over the years on build orientation, and Patrick Hartunian and Mohsen Eshraghi, two researchers from California State University in Los Angeles, are joining the pack.
Hartunian and Eshraghi carried out tensile and fracture toughness tests on the SLM 3D printed samples, along with performing metallography, hardness, and surface roughness analyses. They studied the fracture surfaces and microstructure of the samples using both optical and scanning electron microscopy (SEM) techniques.
The researchers noted that one of the features of SLM 3D printing is the finished roughness of the printing surface, and the sample surface analysis shows that the roughness data of different surfaces is variable. However, when the lateral surface roughness value is high, the top surface of the sample has a relatively smooth feature.