Investigation of accelerated aging effects in phenolic ablative composites

Abstract

C-Phenolic and Si-Phenolic are the special composite materials used for ablative thermal protection in solid motor nozzles for aerospace launch vehicles. These materials are highly specialized composite materials made from C / Si fibres and special phenol-formaldehyde resins. These materials can withstand very high temperature of the order of 1500°C to 3000°C in the nozzle of the solid rocket motors by the principle of self sacrificing and protecting the backend hardware to a very low temperature of the order of less than 100°C when the actual nozzle temperature is of the order of 3000°C. The amount of fibre (C, Si) and the matrix material (phenolic resin) and the different combination plays a key role in the ablative performance. This project deals with preparation of carbon phenolic laminate and subjecting it to accelerated aging conditions to determine the effects of aging on ablative, thermal and mechanical properties of carbon Phenolic for 1yr, 2yrs and 3yrs respectively and comparing the values with an un-aged laminate part. Also, to obtain the defect free specimen and better performance all the specimens are initially gone through non destructive tests viz. ultrasonic and acoustic emission. The components have high specific strength and high stiffness used in aerospace vehicle is made up of light weight materials. In this work, glass fiber reinforced plastic pressure tank is taken for further analysis. These pressure tanks are placed nearer to nozzle which is also affect due to mechanical and thermal effects. These pressure carrying structures are definitely affect during its operating and environmental conditions. Hence, it is necessary to investigate these pressure components during its dynamic stage. newline