Abstract
This paper reviews recent developments in carbon fibers. Intensive studies focus on relationships among processing conditions, chemical/physical structures and tensile properties of polyacrylonitrile and meso-phase pitch based carbon fibers. Carbon fibers with specific geometry, such as hollow, porous, and patterned, have been fabricated for specific applications. Additionally, carbon nanotubes (CNTs), which have excellent mechanical properties, have been processed into macroscopic continuous fibers. Incorporating CNTs in precursor fiber also improves tensile strength and modulus of the resultant carbon fiber. Although extensive studies have been conducted for improving carbon fiber tensile strength and modulus as well as for reducing their production cost, these issues remain amongst the main challenges for broadening their applications.