Popis: |
The porous sound-absorbing material manufactured is light and has excellent heat resistance to be applicable to the exhaust nozzle etc. of a jet engine, can effectively absorb noise as that from a jet engine, over a wide range of frequencies, is free from variations in porosity, and provides stable performance characteristics. An essential feature thereof is the formation of a skeleton of the material, with aggregates containing voids. Thus, a porous sound-absorbing material having a skeleton of aggregates with first voids is described, wherein diameters of first voids of the aggregates are 50 μm to 100 μm, approximately, and diameters of second voids between the aggregates are 100 μm to 600 μm. |