An Insight into the Composite Materials for Passive Sound Absorption

Abstract

In the current scenario of fast growing industrialization sound pollution becomes a key concern that leads to the investigation of novel environmental friendly materials which can absorb sound frequencies in the audible range of 20 Hz to 20 kHz. However, design of passive sound absorbing materials in low frequency (below 500 Hz) regions are still challenging. In the past decade, low frequency noise has begun to be acknowledged as a public health problem. Health concerns lead to high intellectual investments on different types of cost effective, ecofriendly and efficient natural, synthetic as well as nanomaterial based composites to achieve strong wide band acoustic absorption in low frequency range. The composite making technology together with the advancement in nanotechnology paved strong foundation to engineer high performing acoustic materials. These investigations are also prime to the development of phononic crystals, acoustic metamaterials and sound absorbing composites. This review critically investigates the achievements and challenges in passive noise controlling with the help of novel acoustic composite materials.