Surface roughness effect on multiaxial fatigue behavior of additively manufactured Ti6Al4V alloy

Additive manufacturing (AM) is a special technology that offers several advantages compared to the conventional methodologies. For instance, it allows build components with complex geometry, difficult make in different way, integrated parts deleting joining issues, etc. However, its application engineering fields still limited because dependency between mechanical properties of obtained and parameters not depth understood. Improve performances AM components, under static dynamic loadings, crucial ensure their durability reliability recent years became challenging research field. In this work, effect surface roughness on multiaxial fatigue resistance Ti6Al4V thin-walled tubular samples, made by Selective Laser Melting (SLM) process, was investigated. particular, experiments combined axial–torsional loadings were carried out two batches (machined as built samples). Maximum valley Rv used representative parameter geometrically represents stress concentration zone where crack initiates propagates. An effective strain intensity factor range, based modified Smith Watson Topper (MSWT) model, includes Rv, proposed for better correlation data. To prove Socie Reddy & Fatemi strain-based range also but bigger scattering results observed. The MSWT model applied predict failure plane predictions Fatemi-Socie model. Results revealed that, SLM alloy more accurate.