Uniaxial tensile investigation of a porous compound nonwoven fabric

Abstract

Carbon fiber (CF) nonwoven fabric possesses excellent chemical resistance, remarkable electrical properties, and low density, but its mechanical strength must be enhanced to facilitate its application. Therefore, a flexible compound nonwoven fabric (CEF-NF) consisting of CF and a bicomponent polypropylene/polyethylene core/sheath fiber (known as ESF) was prepared using a 2-step wet papermaking/ thermal bonding process. Scanning electron microscopy observations indicated that the CEF-NF fibrous network could be strengthened without blocking its pores by using a heat-pressing temperature falling between the melting regions of the sheath polyethylene and core polypropylene. Additionally, uniaxial tensile experiments were conducted to investigate the failure mode and tensile properties of the CEF-NF by varying the thermal bonding and structural parameters. The results showed that 3 failure modes of fiber physical contact separation, thermal bond breakage, and ESF fracture emerged and could be defined based on the variation in the heat-pressing temperature. The tensile strength of the CEF-NF was improved with increasing thermal bonding and structural parameters. Under a set of process parameters, ie, 180°C heat-pressing temperature, 6-MPa heat-pressing pressure, 40 wt% ESF mass fraction, and 40-gsm areal density, the tensile strength of CEF-NF reached 5.7 MPa, which is much higher than that of pure CF nonwoven fabric.

Significant enhancement of tribological performance of carbon fabric/phenolic composites via interfacial modification and use of a lubricant additive

“…Carbon fabric (CF)/polymer composites are self‐lubricating materials that are widely used in the field of national defense and civil mechanical engineering. [ 1,2 ] They are often used as moving parts (such as bearings, brake discs, tail shafts, and gears) because of their low density, high specific strength, excellent fatigue/corrosion resistance and easy processing. [ 3,4 ] The performance of CF/polymer composites depends largely on the number and large area of complex interfaces between the fiber and resin.…”