On the Melting of Metals

Volume 8, Issue 2, April 2023     |     PP. 15-30      |     PDF (1211 K)    |     Pub. Date: March 19, 2023
DOI: 10.54647/materials430219    63 Downloads     859 Views  

Author(s)

Hasse Fredriksson, KTH (Royal Institute of Technology), Stockholm, Sweden

Abstract
Thermal expansion is related to the atomic vibration amplitude. Owing to the anisotropy in the lattice, the amplitude will vary with the crystallographic direction, causing strain in the lattice. The strain caused by thermal expansion induces a force large enough to initiate plastic deformation of the metal at the beginning of melting. Deformation begins with the gliding of atoms along the gliding direction between two densely packed planes and corresponds to a certain atomic vibration amplitude in that specific direction. Two-dimensional clusters begin to form, and with the input of more energy, melting continues through the formation of three-dimensional clusters and lattice breakage. The heat of fusion corresponds to the energy required to rotate the clusters. When the lattice breaks down, strain energy in the solid is released. This causes a significant decrease in the binding energy between atoms in the liquid state compared to those in the solid state. The volume change during melting is related to changes in the binding energy between atoms in the solid and liquid states. The melting temperature is determined using this theory. The effects of stirring, pressure and gravity on the size of the clusters and melting point are discussed.

Keywords
cluster, heat capacity, heat of fusion, melting, metal, structure, temperature

Cite this paper
Hasse Fredriksson, On the Melting of Metals , SCIREA Journal of Materials. Volume 8, Issue 2, April 2023 | PP. 15-30. 10.54647/materials430219

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