Previous research has demonstrated that production of natural fiber reinforced thermoplastic composites (NFRTCs) utilizing bacterially-derived pure polyhydroxybutyrate (PHB) does not yield a product that is cost competitive with synthetic plastic-based NFRTCs. Moreover, the commercial production of pure PHB is not without environmental impacts. To address these issues, we integrated unpurified ...

A simple method for processing high-performance carbon nanotube (CNT)/poly(vinyl alcohol) (PVA) composites by coupling the spraying of a PVA solution with the continuous winding of CNT sheets from an array onto a rotating mandrel is reported. This method allows the CNT composites to have a high CNT volume fraction, while having a high degree of alignment, long CNTs, and good integration with th...

Supercritical CO(2) has the potential to be an excellent environment within which controlled release polymers and dry composites may be formed. The low temperature and dry conditions within the fluid offer obvious advantages in the processing of water, solvent or heat labile molecules. The low viscosity and high diffusivity of scCO(2) offer the possibility of novel processing routes for polymer...

A study of slow-crack propagation in zirconia-toughened alumina (ZTA) ceramics is presented. Different ZTA composites, using either unstabilized or yttria-stabilized zirconia, have been tested. The materials were prepared in the range 0–15 vol% ZrO2, using two processing methods: powder mixing and a modified colloidal route. Crack propagation tests have been conducted for crack velocities from ...

This article provides a brief overview of several classes of fiber reinforced cement based composites and suggests future directions in FRC development. Special focus is placed on micromechanics based design methodology of strain-hardening cement based composites. As example, a particular engineered cementitious composite newly developed at the ACE-MRL at the University of Michigan is described...

V. Goffaux and B. Rossion (2006) argued that holistic processing of faces is largely supported by low spatial frequencies (LSFs) but less so by high spatial frequencies (HSFs). We addressed this claim using a sequential matching task with face composites. Observers judged whether the top halves of aligned or misaligned composites were identical. We replicated the V. Goffaux and B. Rossion (2006...

Composites are nowadays increasingly used in industries such as aerospace, shipbuilding, automotive ... They are lightweight and have a very high specific stiffness, but defects such as delamination, inclusions may occur during their life cycle. Samples of sandwich honeycomb are tested using a 10 MHz central frequency phased array transducer constituted of 128 elements. Different defects are lo...

The inherent advantages of thermoplastics over the traditional thermoset composite systems are well recognized in the aeronautics community. The main advantages are the much faster processing and the higher toughness. The current advanced thermoplastic material systems provide excellent mechanical performance but their main disadvantage is the difficult processing. Ideally, future aircraft subc...

CoY hexaferrite-filled PEEK (poly ethyl ether ketone) compositeswere synthesized to characterize the effect of hexaferrites on their dielectric, magnetic and thermal properties for wireless sensing and communication applications. Fillers were synthesized from solid-state reaction route and blendedwith the thermoplastic polymermatrix.XRDwas used to study the phase purity of the synthesised fille...

Mono-phase bio-ceramics (alumina and zirconia) are widely used as femoral heads in total hip replacements (THR) as an alternative to metal devices. Unfortunately, the orthopaedic community reports significant in-vivo failures. Material scientists are already familiar with composites like alumina zirconia. Since both are biocompatible, this could prove to be a new approach to implants. This pape...