Ultrasonic wave from high pressure and temperature experiments

The Earth’s inner core shows distinct features, including low shear velocities and a high Poisson’s ratio, often linked to hcp-Fe (hexagonal close-packed iron) through high-pressure experiments and calculations. Premelting is proposed as a key mechanism behind the observed shear softening in hcp-Fe. This study uses magnesium, an hcp-structured analogue, to explore the effects of premelting on ultrasonic velocities. Premelting begins at ~0.97 times the melting temperature(Tm), leading to sharp nonlinear drops in shear (VS) and compressional (VP) velocities by 14.5% and 4%, respectively, with a ~13.3% increase in Poisson’s ratio. These findings, together with seismic and mineralogical data, suggest that premelting could account for the reduced VP and VS and increased Poisson’s ratio observed in the Earth’s inner core., , , # ultrasonic wave from high pressure and temperature experiments

[https://doi.org/10.5061/dryad.dv41ns27z](https://doi.org/10.5061/dryad.dv41ns27z)

## Description of the data and file structure

This data are used for paper \"Profound Impact of Premelting in the hcp-Structured Earth's Inner Core\". This data continue the experiments records (records.xlsx) and the travel time of ultrasonic wave (Ultrasonic wave For P-wave and Ultrasonic wave For S-wave) at different temperature.

### Files and variables

#### File: data.zip

**Description:** 

**Experimental_records.xlsx** contains a detailed log of the experimental procedures during ultrasonic wave measurements. It includes the time, temperature, file number, travel time, and heater power for each ultrasonic measurement. 

**Time**: The timestamp when the data was recorded.

**Temperature(degree centigrade**): The sample temperature at the time of recording.

**Frequency (Hz)**: The frequency of the ultrasonic wave used.

**S-NO**: The ...,