Cliff Wood
Advisor: Prof. Satish Kumar

will propose a doctoral thesis entitled,

Processing and Properties of Novel Carbon Fibers with Non-uniform Cross-sections from Polyacrylonitrile-based Precursors  

On

Thursday, September 25 at 1:30 p.m.
MRDC Room 3515

Committee
            Prof. Satish Kumar – School of Materials Science and Engineering (advisor)
            Prof. Donggang Yao – School of Materials Science and Engineering
            Prof. Karl Jacob – School of Materials Science and Engineering

            Prof. Youjiang Wang – School of Materials Science and Engineering
            Prof. Kyriaki Kalaitzidou – School of Mechanical Engineering

Abstract

    Carbon fibers are often utilized as a structural material in pursuit of greater efficiency. Their exceptional strength-to-weight ratio makes them especially desirable for specialized, high-performance applications, where weight or volume is critical, but this is also beneficial in a wide variety of mundane structures. The primary barrier to implementing carbon fibers is their high cost, stemming from expensive feedstocks and energy-intensive processing. The introduction of new and novel fiber structures would help meet these efficiency goals, whether in terms of further improving the specific strength and stiffness of the fibers or reducing production costs such that they can be introduced to other industries. Currently, many of these alternative processes have not been developed to the same extent as conventional fibers, and improving the understanding of the processing-property relationships in these novel fiber systems will be vital to their commercial introduction. This work focuses on two such novel systems; fibers containing carbon black and multichannel hollow carbon fibers. The inclusion of carbon black into polyacrylonitrile fibers results in a porous structure that has been shown to stabilize significantly faster than conventional fibers; thus, cost is reduced both in the feedstock and processing of the fibers. Further work in this fiber system will determine the effect of the porosity on the rate of oxidation versus cyclization in the stabilization process, as well as the mechanical properties, density, and porosity after carbonization with varying degrees of stabilization. Similarly, work on the multichannel hollow carbon fibers will show how the degree of stabilization before carbonizing affects the specific properties of the fibers, as well as potentially generating novel morphologies. The hollow carbon fibers will also be processed into composite laminates, such that the composite quality can be assessed relative to conventional fiber laminates using commercial non-destructive analysis as well as mechanical testing to determine potential structural gains.