Melting Temperature of Iron in the Core, Experimental
There are two major techniques commonly used for ultrahigh pressure melting studies: shock wave experiments and the internally heated diamond anvil cell (DAC). In shock compression experiments, the sample is subjected to high pressures and high temperatures by dynamic processes (see Shock wave experiments). In DAC experiments, pressure is generated by pressing two opposing diamond anvils, while heating is applied resistively and/or using laser heating. Both techniques have been extensively applied to study high pressure melting of iron. However, accurate determination of melting is exceedingly difficult at extremely high pressure and temperature conditions. The associated weaknesses—the short timescale in shock compression and the small sample size in DAC—are reflected by the large uncertainties and the discrepancy among literature values on melting temperature of iron in the core.
In this section, we begin with a brief description of the generation of simultaneous high...
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