Influence of surface characteristics and finishing on fatigue properties of additively manufactured Ti6A14V

Additive manufacturing, also known as 3D printing, is one of the rapidly developing technologies for producing objects with complex geometry. This is particularly advantageous in the medical industry due to the processing potential of titanium-based biocompatible alloys. This allows the manufacture of implants with geometries that are not possible to produce with conventional methods. One of the biggest disadvantages of 3D printing is the surface of the print with high roughness and support structures that must be removed after the production process. In order to improve these parameters, mechanical processing is usually used, which is very time-consuming and does not allow the element to be processed in hard-to-reach places. The article presents an innovative method of surface finishing and removal of support structures of elements printed using Selective Laser Melting (SLM) technology with the use of a bath in HF / HNO3 solution assisted by ultrasound. The influence of the process parameters on the surface quality and material loss were presented, and the parameters of the fatigue strength of the printed samples were compared: as printed, after additional turning, and after using the ultrasonic surface finishing method. The results showed that with the use of the above-mentioned technology, the fatigue strength of the material increases significantly due to the reduction of surface roughness.