A method for preparing a carbon / carbon composite material, a silicon-containing hydroxyapatite coating

The invention provides a preparation method of a silicon-containing hydroxyapatite coating of a carbon/carbon composite material. The preparation method comprises the following steps: placing a low-density carbon/carbon composite material in a hydrothermal kettle containing a sodium perchlorate solution for hydrothermal treatment, and then washing with distilled water and drying the carbon/carboncomposite material; placing the treated carbon/carbon composite material in a flowable aqueous solution containing calcium nitrate and ammonium dihydrogen phosphate, and precipitating out a calcium hydrophosphate coating on the surface of the carbon/carbon composite material through an ultra-high frequency electromagnetic induced heating method; then placing the calcium hydrophosphate coating of the carbon/carbon composite material in the hydrothermal kettle containing an ammonia water aqueous solution for hydrothermal treatment so as to obtain the hydroxyapatite coating of the carbon/carbon composite material; and subsequently, placing the hydroxyapatite coating of the carbon/carbon composite material in the hydrothermal kettle containing a sodium silicate aqueous solution for hydrothermal treatment again so as to obtain the silicon-containing hydroxyapatite coating of the carbon/carbon composite material. By using the method, the silicon-containing hydroxyapatite coating with good crystallinity, high bonding strength up to critical load 143 N and Vickers hardness 2.3 can be prepared on the surface of the low-density carbon/carbon composite material.