Pressure dependence of the melting temperature of metals
Abstract
We present a new method for the analysis of the experimental data for the pressure dependence of the melting temperature of metals. The method combines Lindemann's law, the Debye model, and a first-order equation of state with the experimental observation that the Grüneisen parameter divided by the volume is constant. We observe that based on these assumptions, in the absence of phase transitions, plots of the logarithm of the normalized melting temperature T'=(Tm/Tm0X2) versus the logarithm of the normalized pressure P'=1+βP are straight lines with slope 2γ0/α Tm0 is the zero-pressure melting temperature, X==(V/V0)1/3, γ0 is the Grüneisen parameter at Tm0, α==B'0+1, β==α/B0, where B0 is the isothermal bulk modulus at Tm0, and B'0 is the pressure derivative of B0 at Tm0. We find that the normalized-melting-temperature-versus-normalized-pressure curves accurately satisfy this linear relationship for Al, Ag, Au, Cs, Cu, K, Na, Pt, and Rb. In addition, this technique provides a sensitive tool for detecting phase transitions.
- Publication:
-
Physical Review B
- Pub Date:
- September 1989
- DOI:
- 10.1103/PhysRevB.40.5929
- Bibcode:
- 1989PhRvB..40.5929S
- Keywords:
-
- 64.10.+h;
- General theory of equations of state and phase equilibria