Studies On Properties Of Charring Layer Insulation

The characterizations of the insulation charring layer are defined by investigating the charring layer with good insulating and ablative properties that is formed by ablating the solid rocket motor insulation. The charring layer that is investigated is prepared by using high temperature and pressure method, ablative experimental device and ablative simulation motor. The thermal conductivity of the charring laryer is tested by hot plate and laser flash method, the specific heat of the charring layer is tested by DSC. Thermogravimetry and high temperature and pressure method test charry rate of the charring layer, elemental analysis and EDS test chemical composition of the charring layer.the shaoshi A sclerometer tests hardness of the charring layer, mechanical characteristics of the charring layer is tested by nanoindention technology. The structure and surface morphology of the charring layer are analysed by cutting the surface images with the digital cameras, SEM, the microscope, XRD analyses crystallization of the charring layer, the pore diameter and distribution of the charring layer are measured by the statistical method and mercury intrusion method, the results of mercury intrusion method are amended are as same as the statistical method on the pore diameter, the specific surface area of the charring layer is measured by BET, mercury intrusion method or calculating with statistical method, and the law of the specific surface area is derived to S=6η/(ρΦ). It is the basis and bridges for analysing ablative mechanism, building ablative model and studying new solid rocket motor insulation materials that properties of the charring layer are investigated.