Relation Between Solid-State Amorphization and Melting

1 Relation Between Solid-State Amorphization and Melting 

Solid-state amorphization can be induced through a variety of methods including irradiation, chemical reactions, mechanical-deformation techniques, pressure application, etc., as discussed above. As such, a crystalline phase can be driven into a disordered amorphous state as long as the kinetic constraints inhibiting stable phase formation can be maintained. 

It is generally agreed that thermally induced vibrations of atoms in solids play a major role in melting [2.144]. The simple vibrational model of Linde-mann predicts a lattice instability when the root-mean-square amplitude of the thermal vibrations reaches a certain fraction / of the next neighbor distances. However, the Lindemann constant/varies considerably for different substances because lattice anharmonicity and soft modes are not considered, thus limiting the predictive power of such a law. Furthermore, Born proposed the collapse of the crystal lattice to occur when one of the effective elastic shear moduli vanishes [2.138], Experimentally, it is found instead that the shear modulus as a function of dilatation is not reduced to zero at Tm and would vanish at temperatures far above Tm for a wide range of different substances [2.145] 

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