Perhaps late to the thread, but turbine blades with internal cooling channels are one of the dream applications for metal additive manufacturing, though I'm not

Perhaps late to the thread, but turbine blades with internal cooling channels are one of the dream applications for metal additive manufacturing, though I'm not sure it may ever be realizable. If you could lower the operating temperature of the turbine blade in this way, you might be able to mitigate the risk of creep, which as sibling posters point out is the motivation for the use of single-crystal turbine blades and thermal barrier coatings. There's a lot of buzz in the materials community around additive, but I think 3D-printed turbine blades are basically just a dream right now. People are still wrestling with getting consistent build quality for simple structural components...