Whizzjet,
Not all turbine blades are single crystal. Depending on engine type and generation, and where the blades sit in the engine (high, intermediate, or low pressure), they may be single crystal, directionally solidified (polycrystalline with logitudinally aligned boundaries and no transverse boundaries), or equiaxial, with differing amounts of grain boundary strengtheners and different alloying elements.
The chemistry/physics/metallurgy of turbine blades is actually quite interesting, including oxidation, corrosion, creep and fatigue, and processing considerations.
Oh, and like you, before I went to college, I couldn't even spell metaLLurgist, and now I are one
