铸石吸声板材料开发与应用研究

铸石吸声板是利用聚氨酯作为载体,以铸石粉、添加剂、水和胶搅拌成的浆料,涂挂于载体上,通过振动后自然固化而制成。制成后的吸声板具有刚性、开孔的特性,且孔孔相连、通透。考察不同厚度、孔径的载体对铸石吸声板吸声系数的影响。结果表明,在相同孔径的前提下增加载体的厚度可以提高对中低频吸声系数,而对高频吸声效果影响较小。厚50mm的铸石吸声板NRC达到0.60,吸声性能达到Ⅱ级。

Development and Application of Sound Absorption Casting Board

Acoustical casting board is made of a new composite material for sound absorption purpose.In the manufacture of this board,a polyurethane board is taken as a carrier.Then,it is coated by mixed cream including some basic components such as casting powder,additives,water and gelatin.After vibration consolidation process,this board is solicited in the natural environment.The acoustical casting board has the merits of high stiffness,porosity and open pores.In this paper,the influence of board thickness and pore dimensions on the sound absorption coefficient of the board is studied.It is shown that increasing the board thickness with the pore dimension unchanging can raise the sound absorption coefficient for medium and low frequencies,but has small influence on the sound absorption coefficient for high frequency.The NRC of the board of 50mm thickness can reach 0.6,and the property of sound absorption can reach grade Ⅱ.