New answers tagged crystals
I am not sure thermal expansion is much greater in polycrystals than in single crystals (http://nvlpubs.nist.gov/nistpubs/jres/14/Jresv14n5p523_A1b.pdf, Fig. 13). Wikipedia article that you quote says that single crystals have higher creep strength at high temperatures, so they can provide higher turbine efficiency.
Single crystal jet turbine blades are grown in a substantially different way than most crystals. The following article gives details of some of the R&D and large scale production process that is used. http://www.tms.org/superalloys/10.7449/1980/superalloys_1980_205_214.pdf
Okay so admittedly I know nothing about jet turbines, however I know a little something about crystals. The occupied lattice points of a single crystal are interacting with good overlap of atomic orbitals. If you have a d-block metal then you get the standard d-d and d-p interactions as predicted by tight binding and Hubbard models. Grain boundaries are ...
Engineers usually treat thermal expansion as isotropic, which means the expansion occurs with the same magnitude in every direction. This means that an unconstrained object will have a constant strain and zero stress associated with thermal expansion, it's as if object just scaled up. However, as you suspected, materials with an organized structure can be ...
Careful! The essence of your question is a good thought but I think you are having several misconceptions. First of all, it doesn't make sense to talk about a phonon being directed towards a single atom. Phonons are delocalized. Secondly, the "input of temperature required to eject an electron" is a dangerous idea. You need to input energy to eject an ...
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