Void damage model and service life prediction for solid high polymer

Based on the analysis of three void damage variety models, this note presen ts (i) a method that regards the void content as a damage variation of the grain and (ii) a geometric model for micro-unit of void damage. Equations o f the void damage variety containing void content are analyzed. This work i s focused on the measurement of internal damage level and the damage variet y estimation is directly related to the life predication in the practical e ngineering applications. Nowadays, the critical service life of the solid g rain/polymers is usually presumed at domestic and international level. The strength or strain reduction of 20% or the stabilizer consumption of 50% is generally regarded as a critical storage life of the solid grain/polymers, and the service life is predicted by the extrapolation method on Anhenius formula. The applications, however, show that the above method is unreliabl e and has significant errors. With the aid of the discontiguous automatic m easuring device of real time volume deformation and void content, the maste r curve of void damage variety, the storage service life and the surplus li fe of a solid rocket grain are obtained. Since the critical storage life ha s been measured, and the accuracy of the service life prediction has been g reatly increased. It is a novel ideal and a break-through technique.