An iron foam/silica aerogel composite (IFSA) with bimodal structure was designed and fabricated to solve the contradictions between acoustic damping and mechanical strength of a material. IFSA exhibits excellent broadband sound absorption performance with average absorption of ∼57% (500–6400 Hz) and maximum absorption coefficient of 0.995 at 4336 Hz, and high specific stiffness (1.6 × 105 m2 s−2). The dissipation mechanism of sound energy in IFSA is well predicted by a designed bimodal model. Such fascinating artificial composite not only provides new insights for developing structural materials with high noise reduction and strength, but also has great potential applications for various fields.

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We synthesized the copper foam sustained silica aerogel (CFSA) by sol-gel transition followed by CO2 supercritical drying. The as-prepared CFSA exhibits excellent sound absorption capability and favorable compressive properties. Incorporation of epoxy resin during sol-gel process can improve the combination between silica aerogel and copper foam framework, which helps to significantly increase the average sound absorption from ∼36% to ∼55% (200-3900 Hz) and the maximum sound absorption coefficient from 0.78 to 0.99. A high Young’s modulus of ∼11.01 MPa and compression strength of ∼0.30 MPa were demonstrated for CFSA as well. The fabricated CFSA also shows some advantages, e.g., lightweight (density of 0.28 g/cm3) and hydrophobic. Such fascinating artificial composite may provide new insights into the development of strong and effective aerogel sound-absorbing materials for various applications.