固体发动机界面粘接性能的非线性超声无损评价

Nondestructive evaluation on adhesive properties of SRM interface using nonlinear ultrasonic

壳体/绝热层界面衬层的粘接性能会影响固体发动机最终性能。基于超声纵波透射法,结合衬层样本的红外光谱图,研究衬层固化过程中超声非线性系数与微观组织结构间的关系。铌酸锂晶片的滤波特性,有效减少前端仪器的非线性,提高了测量数据的鲁棒性。实验结果表明,随着固化度增加,超声非线性系数逐渐减小,界面粘接性能越好。因此,利用超声非线性系数,可对界面的粘接性能进行超声无损评价。

Adhesion properties of the liner between case and insulation of SRM will affect the performance of final product.The relationship between ultrasonic nonlinearity and microstructure of the liner was studied during the whole curing process by ultrasonic transmission method and infrared spectroscopy.The nonlinearity of input instrumentation was minimized by the natural filtering effect of piezoelectric discs and hence making the measuring data more robust. The experimental results show that ultrasonic nonlinearity coefficient is decreased and adhesive properties of interface are enhanced as the curing degree increases.The research suggests an effective nondestructive approach to evaluate the adhesive properties of interface in a nonlinear ultrasonic way.