Natural fiber-reinforced composites: A review on material, manufacturing, and machinability

Interest in natural fiber-reinforced composites (NFRCs) is increasing rapidly thanks to their numerous advantages such as low cost, biodegradability, eco-friendly nature, relatively good mechanical properties, and a growing emphasis on the environmental and sustainability aspects of engineering materials. However, large-scale use of NFRCs is still considered as challenging due to the difficulties in manufacturing, limited knowledge of its machinability and appropriate parameter settings, and being prone to machining-induced defects. This article presents a comprehensive review on various aspects of NFRCs, with a focus on the manufacturing and machinability. It covers some recent works related to NFRCs, including the manufacturing processes and parameters, characterization of mechanical properties, applications, and machinability and machining process monitoring, many for the first time. The main challenges associated with machining of NFRCs and the induced damages are outlined, with special attention paid to the effect of physical properties of the fibers and manufacturing process on the machinability, along with the essential machining parameters that affect the quality of the machined surface. The research perspectives and the current application status are also discussed. The article is intended to help readers attain a fundamental understanding of key technologies and the state of the arts in this research area.