The invention relates to the field of under-pressure downhole operation of oil and gas wells, in particular to a
glass ceramic material, a plug core and a preparation method thereof.The
glass ceramic material is prepared from, by mole, 6%-15% of Li2O, 60%-75% of SiO2, 6%-12% of Al2O3, 0-1% of K2O, 1%-3% of Na2O, 1%-3% of P2O5, 0-1% of ZrO2, 0-2% of CaO and 0-3% of CeO2, the
mass ratio of Al2O3 to Li2O in the components is adjusted, controllable heat treatment
crystallization is carried out, and the
glass ceramic material is prepared. Two crystals of Li2Si2O5 and beta-
spodumene can be separated out at the same time, the excellent
mechanical property of Li2Si2O5 and the excellent
thermal expansion property of beta-
spodumene are combined, the using performance of a plugging tool in an underground oil
pipe is met, meanwhile, due to the fact that the glass phase content is high, the
brittleness is large, compared with an aluminum
oxide ceramic material, the glass phase is very easy to crush, fragments are uniform
small particles and have no sharp corners, and the service life of the plugging tool is prolonged. And the full bore of the oil
pipe is effectively guaranteed, and the risk of pipeline
scratching is avoided. The problems that in the prior art, a plug core is low in strength, and potential safety hazards are large due to the fact that broken fragments are sharp-corner fragments are solved.