Melting
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Physics
Mechanical failure modes |
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Buckling |
Corrosion |
Creep |
Fatigue |
Fracture |
Melting |
Thermal shock |
Wear |
In physics, melting is the process of heating a solid substance to a point (called melting point) where it turns liquid. An object, which has melted, is molten. Freezing is the opposite of melting. It is the process of turning a liquid to a solid. Consequently the freezing point is the same temperature as the melting point. See the phase article for more detail.
Not only the heating to the melting point, but also the melting itself requires heat, see latent heat.
From Thermodynamics point of view at melting point the change in Gibbs Free Energy (ΔG) of the Material is zero, because the enthalpy (H) and the entropy (S) of the material are increasing (ΔH,ΔS>0). Melting phenomenon happens when the Gibbs free energy of the liquid becomes lower than the solid for that material. At various pressures this happens at a specific temperature. We can also show:
ΔS=ΔH/T
The "T","ΔS", and "ΔH" in the above are respectively the temperature at the melting point, Change of entropy of melting, and the change of enthalpy of melting.
Genetics
In genetics, melting DNA means to separate the double-stranded DNA into two single strands by heating or the use of chemicals.
- See also : Polymerase chain reactioncs:Tání
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