Numerical, Mechanical, and Metallurgical Investigation of an Innovative Near Net Shape Titanium Selective Laser Melting Engine Component and Comparison with the Conventional Forged One

Selective laser melting (SLM) can be used to manufacture near net shape (NNS);the main benefits are a remarkable weight reduction, a lower environmentalimpact, the opportunity to integrate some functions, and an improvement of theperformances. The current article covers the development of a Ti6Al4V NNS enginecomponent produced by SLM. Finite element analyses of the main relevantoperating conditions are performed to reach a topological optimization of the part.The main target is weight reduction keeping the same safety performances. Theweight reduction achieved is 45% and 15% with respect to steel and titaniumforging by replacing the original“H”section with an SLM multibranch structure.Other benefits are the manufacturing of the connecting rod (conrod) into twoseparate parts, avoiding the difficult machining to separate the cap from the mainbody and the integration of conformed cooling channels into the conrod. Then, theSLM components are produced and mechanical and metallurgical properties areinvestigated and compared with the titanium hot forging ones. Both the macro-structures present equiassic and isotropic behavior due to the heat treatmenttransformation. No defects are observed for both the technologies. The mechanicalproperties are verified to be aligned with the design targets.