|MadSci Network: Engineering|
in principle you can fuse any elements you want. The energy required for fusion is provided by the temperature of the plasma. The energy is needed to overcome the electrostatic repulsion of the atomic nuclei which are to be fused. The heavier the nuclei (in fact, the more protons they have) the higher temperature we need. Therefore, we have to concentrate on light elements. The needed temperature is lower and also the requirements on the materials of the fusion device. The fusion of heavy elements is therefore also from a technical point of view not realistic.
In nature elements are produced by fusion in stars, but only up to Fe. The fusion of higher elements is not achieved in stars, since no energy can be gained. That is the thermal energy needed to fuse those elements is higher than the energy gain. Therefore, this is also technically not interesting. Heavier elements are produced in supernova explosions.
best regards, Michael
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