SUN Jinxing, LIU Peisheng, CHEN Bin
(Key Laboratory of Beam Technology and Material Modification of Ministry of Education, College of Nuclear Science and  Technology, Beijing Normal University, Beijing 100875, China)

Abstract: Porous ceramics were successfully prepared by conventional molding with pore forming agents. Using JTZB absorption coefficient test system the sound absorption coefficient of porous ceramics was tested and the average sound absorption coefficient was calculated. The sound absorption performance of porous ceramic was optimized by an orthogonal experiment table with four factors and three levels of values including thickness, porosity, aperture size and the depth of cavity. Results show that porous ceramics have excellent sound absorption performance at the low and intermediate frequencies while the sample thickness is 25 mm, the porosity is 73.5%, the aperture size is 4-5 mm,and the cavity thickness is 20 mm. The primary and secondary factors influencing the sound absorption performance of porous ceramics were acquired by the method of variance analysis.

Key words: porous ceramic; average sound absorption coefficient; porosity; orthogonal experiment