Research on characteristics of microstructure and acoustic emission of marble in the heating process

In this paper, a detailed analysis is made to detect the morphology of Xuzhou marble from room temperature to 1400 degrees using polarizing microscope and combine it with acoustic emission characteristic parameters from 200 degrees to 800 degrees. Some results are achieved: the marble samples would produce strong acoustic emission phenomena affected by high temperatures that the acoustic emission ring count rate increases with increasing temperature and acoustic emission activity becomes more frequent in the heating process. There is a corresponding relationship between rock acoustic emission characteristic parameters and its internal crack network formation. The ringing cumulative number of marble increases with increasing temperature which indicates that the internal cracks continue to expand with increasing temperature while it changes rapidly at two temperature ranges which are 200 degrees to 400 degrees and 600 degrees to 800 degrees indicating that 400 degrees is the threshold value of crack growth and the cracks fully expand and format large transcrystalline cracks at 800 degrees.