The study of the mechanical interaction among the host, interface, and a device embedded within a laminated composite is important. Embedding micro-sensors in composite laminates produces material discontinuity around the inclusions. This in turn produces stress concentrations at or near the inclusions. Both 2D plane strain and 3D FEM models are developed to analyze the stress/strain state surr...

Two polyimide-matrix systems were subjected to a series of hygrothermal aging experiments at various temperatures and relative humidities. For each aging condition, we measured the microcracking fracture toughness as a function of aging time. The toughness decreased with time. The rate of decrease increased with temperature and relative humidity. All experimental results could be fit to a simpl...

Tetrahydrobiopterin, the cofactor required for hydroxylation of aromatic amino acids regulates its own synthesis in mammals through feedback inhibition of GTP cyclohydrolase I. This mechanism is mediated by a regulatory subunit called GTP cyclohydrolase I feedback regulatory protein (GFRP). The 2.6 A resolution crystal structure of rat GFRP shows that the protein forms a pentamer. This indicate...

Experimental design and response surface methodology (RSM) were used to optimize the modification of conditions for glass surface grafting with acrylamide (AM) monomer for preparation of a glass fiber reinforced poly(vinylidene fluoride) (PVDF) composite membrane (GFRP-CM). The factors considered for experimental design were the UV (ultraviolet)-irradiation time, the concentrations of the initi...

The prerequisite for more competent and cost effective transport has led to the evolution of innovative testing and evaluation procedures. Non-destructive testing and evaluation (NDT & E) techniques for assessing the integrity of composite structures are essential to both reduce manufacturing costs and out of service time of transport means due to maintenance. Smart methods for assessing the in...

A major concern affecting the efficient use of carbon fibre reinforced composite laminates in the aerospace industry is the low velocity impact damage which may be introduced accidentally during manufacture, operation or maintenance of the composite structures. It is widely reported that the contact behavior of composite laminates under low-velocity impact can be obtained under quasi-static loa...

Composite sandwich materials have yet to be widely adopted in the construction of naval vessels despite their excellent strength-to-weight ratio and low radar return. One barrier to their wider use is our limited understanding of their performance when subjected to air blast. This paper focuses on this problem and specifically the strength remaining after damage caused during an explosion. Carb...

Chirped fibre Bragg grating (CFBG) sensors have been embedded within the adhesive bondline of single-lap bonded composite joints, fabricated using a transparent glass fibre reinforced plastic (GFRP) adherend bonded to a carbon fibre reinforced plastic (CFRP) adherend. During fatigue cycling, disbonds initiated adjacent to the cut ends of one, or both, of the adherends and the disbonds propagate...

Drilling is one of the important machining processes in hole making operations. Delamination is a vital problem during any drilling operation. It causes structural integrity reduction and poor assembly tolerance as well as potential for long-term performance deterioration. As a result, drilling of any material requires dimensional stability and interface quality. In this study, glass fibre rein...

Glass fiber-reinforced polymer (GFRP) ship structures have hull plate thicknesses of 10 mm or more and are fabricated using a higher proportion resin matrix systems than E-glass fiber reinforcements. Therefore, GFRP is classified as highly attenuative material, this characteristic major cause large errors in ultrasonic nondestructive testing for quality inspections. In study, considering the af...