This Dataset contains the measurement data of the related publication Ruf & Steeb (2022). In this, twelve thermal treatments, differing in the applied maximum temperature and the applied cooling condition (slow versus fast cooling) are experimentally studied for dry Bianco Carrara marble under ambient conditions. Three sizes of cylindrical core samples with identical aspect ratios are investigated to identify a potential size effect.

All samples were extracted by water-cooled diamond drilling from Bianco Carrara marble blocks. The 39 medium-sized samples (3 per thermal treatment + 3 for reference purposes) were extracted from two 80 mm thick blocks, the 13 small samples (1 per thermal treatment + 1 for reference purposes) from one block with 40 mm thickness, and the 13 large samples (1 per thermal treatment + 1 for reference purposes) from one block with 125 mm thickness. Drilling orientation of all medium and small samples was chosen identical. The drilling orientation of the large samples is different compared to the other two samples sizes. Based on the characterization of the specimens, no significant differences were found between the four blocks. The medium-sized cylindrical core samples were reworked to a final diameter of 29 mm and a length of 72.5 mm, the small samples to a diameter of 12 mm and a length of 30 mm, and the large samples to a diameter of 48 mm and a length of 120 mm employing a lathe.

The 12 different thermal treatments involve three steps:

Heating-up from Room Temperature (RT) to the maximum temperature Tmax = {100, 200, 300, 400, 500, 600}°C with a constant, relatively low heating rate of 3 K/min to avoid bigger temperature gradients inside the samples. Holding of Tmax for 120 min to achieve a uniform temperature distribution inside the samples. Cooling the samples back to RT by slow or fast cooling protocol. The slow cooling was performed in the switched-off, closed furnace and the fast cooling by quenching the samples in a large water basin at RT.

To refer to the different thermal treatments, the maximum temperature Tmax in degree Celsius followed by the term "slow" or "fast" is used. The 12 characteristic temperature profiles inside the furnace are provided in "thermal_treatments_furnace_temperature_profiles.tar.gz".

The characterization of each sample was done before and after the respective thermal treatment. For this, on the one side, the geometry (diameter and length) and mass were measured. Based on these results, the bulk volume and bulk density were derived. On the other side, the ultrasonic wave speeds (P- and S-wave) were determined by performing ultrasonic through-transmission measurements. All samples were investigated in the dry state and under ambient (laboratory) conditions. Classical oven drying was deliberately not done to avoid any potential influence. Instead, all samples were dried for several days under ambient conditions between the different steps of the measurement workflow. To label the samples, the following key is used: the maximum temperature of the thermal treatment, the cooling method (slow versus fast), the value of the nominal diameter in millimeter, and a continuous sample number for the specific thermal treatment. Within the file names, the measurement point before the respective thermal treatment is indicated by "t0" and after by "t1".

The files "processed_data_absolute_values_t0.csv" and "processed_data_absolute_values_t1.csv" contain all absolute measurement data derived from the different measurements. The file "processed_data_relative_changes.csv" contains the relative changes resulting from the respective thermal treatment. Since significant shear wave splitting was observed in the thermally treated samples compared to the untreated samples, the shear wave measurements were performed at different polar angles for the treated samples. The file "processed_data_absolute_values_polar_measurments.csv" includes the respective measurements.

The raw ultrasonic measurement data (transducer signals over time) from the ultrasonic through-transmission experiments is provided for all samples ("medium_samples.tar.gz", "small_samples.tar.gz", "large_samples.tar.gz"). The .psdata files can be opened with the free software "PicoScope 6 - PC Oscilloscope Software". The averaged signal of a stack of 32 signals is provided in the corresponding .csv file. The system times for the ultrasonic measurements were experimentally determined based on measurements of two aluminum (Al) standards with 50 mm and 100 mm lengths ("aluminum_standards.tar.gz").

For further details about the measurements, cf. the related publication Ruf & Steeb (2022).