Abstract: In order to analyze two basic acoustic characteristic parameters of activated carbon fiber materials: propagation constant and characteristic impedance, propagation theory of acoustic waves in activated carbon fiber materials is used for reference and equations of motion and continuity are used for deduction, thus theoretical model of propagation constant and characteristic impedance is established. Surface acoustic impedance is tested with an impedance tube when activated carbon fiber materials are put in the 250-2500Hz frequencies acoustic range, then propagation constant and characteristic impedance of activated carbon fiber materials are defined by the method of double thickness. Statistics of two acoustic characteristic parameters in theory and trial are compared and contrasted, which shows that the theoretical model has its feasibility and can provide reference for developing and designing the activated carbon fiber materials with acoustic characteristics.

Key words: activated carbon fiber, characteristic impedance, propatgation constant, acoustic characteristic, surface acoustic impedance