Siemens Energy AB is leading the energy transition by developing cutting-edge technologies to make this shift faster. This thesis work focuses on gas turbines and the approaches involved in the company’s current R&D efforts. Additive Manufacturing (AM) is becoming a very interesting technology for the design of gas turbine cooling channels enabling the production of very complex geometries at a relatively low cost. AM has the potential to replace the conventional manufacturing methods, thereby increasing the operational life of the component, reducing maintenance operations and boosting the performance of the machine. The key aspect of AM is the surface roughness (SR) originating during the process, which can significantly enhance heat transfer mechanisms.