A diagram of directional solidification based on an image from <a rel="nofollow" class="external autonumber" href="https://books.google.com/books?id=3O5kqZww24gC&amp;pg=PA104">[1]</a>.
<a href="//commons.wikimedia.org/wiki/User:Wizard191" title="User:Wizard191">Wizard191</a>
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