Sound Insulation Properties of Stainless Steel Fiber Porous Materials with Complex Structure

Stainless steel fiber felt with 8 mu m in thickness was used as raw material, and stainless steel fiber porous material with different porosities, average pore sizes and thicknesses were prepared by volume-weighing method and high temperature sintering. Positive gradient structure, inverse gradient structure and film composite structure were designed by structural optimization. The sound insulation performance of the three kinds of the structures was tested, and the sound insulation characteristics of the structures were studied. The sound insulation results indicate that the stainless steel fiber porous material has a certain sound insulation performance. When the thickness is 20 mm, the porosity is 85%, the average sound insulation of the stainless steel fiber porous material is 18.92 dB in the frequency range of 50-6400 Hz. The lower the porosity, the smaller the average pore size, the thicker the thickness, the better the sound insulation performance of the material. The sound insulation performance of the designed positive gradient and the inverse gradient structures is worse than the single layer stainless steel fiber porous material. The sound insulation performance of the stainless steel fiber porous composite material with film material is greatly improved at medium and high frequencies. When the thickness is 20 mm, the average sound insulation is 27.86 dB, and the highest is increased by 16.96 dB.