Damage and fracture mechanisms of two 2198 Al-Li thin sheet alloys having different thicknesses (2 and 6 mm) are investigated. Two heat treatments are studied: T3 and T8. Mechanical tests are carried out on flat specimens including smooth tensile samples and U-notched specimens (with various notch radii). Test data are used to identify the parameters of constitutive equations describing plastic...

A compact printed ultra wideband (UWB) monopole antenna with multi-notched characteristics is presented. By inserting multiple E-shaped slot in micro strip feed line and ground plane, additional resonances are excited. The multi notch has been created by embedding a pair of – L shaped arm in the radiating patch and a modified E-slot defected ground structure in the feeding line. The designed an...

We present a compact ultra-wideband (UWB) antenna integrated with sharp notches with a detailed analysis of the mutual coupling of the multiple notch resonators. By utilizing complementary split ring resonators (CSRR) on the radiating semi-circular patch, we achieve the sharp notch-filtering of various bands within the UWB band without increasing the antenna size. The notched frequency bands in...

Two groups of PLGA specimens with different geometries (notched and unnotched) were injection molded under two melting temperatures and flow rates. The mechanical properties, morphology at the fracture surface, and residual stresses were evaluated for both processing conditions. The morphology of the fractured surfaces for both specimens showed brittle and smooth fracture features for the major...

The present paper is concerned with modelling damage and fracture in notched woven fabric composites. Previous experimental work has shown that damage at a notch in a variety of GFRP and CFRP composites based on woven fabric reinforcement comprises matrix damage and fibre tow fracture along the plane of maximum stress. It is these experimental observations that inform the failure modelling deve...

Ultra Wideband (UWB) is a new emerging and promising technology as it can accommodate higher data over a large bandwidth. we proposed a Printed Square-shape UWB Antenna With Dual Band-Notched Characteristics. A simple square patch antenna has been fed through a 50 Ω microstrip feedline .A rectangular notch has been etched on the ground plane to reject the interference of WIMAX Band (3GHZ-4.7GHZ...

Precracked and notched specimens were used to investigate the fracture mechanism of a bainite steel at low temperature. The critical fracture event was studied using metallographic sectioning method. The results showed that the critical cleavage event was different in the precracked and the notched specimens. At -196C, all specimens fractured at lower-shelf region without any ductile crack grow...

The present paper is concerned with modelling damage and fracture in notched woven fabric composites. Previous experimental work has shown that, under tensile loading, damage at a notch in a variety of GFRP and CFRP composites based on woven fabric reinforcement comprises matrix damage and fibre tow fracture along the plane of maximum stress. It is these experimental observations that inform th...

A compact ultra-wideband (UWB) bandpass filter with high selectivity and deep notched band attenuation is presented in this letter. The main structure of this filter is a balun-based coplanar waveguide (CPW)-microstrip CPW transition. This structure has UWB bandpass characteristic (2.85– 11GHz) and a transmission zero at its lower transition band. To achieve a transmission zero at its upper tra...

generally, fatigue failure in an element happens at the notch on a surface where the stress level rises because of the stress concentration effect. the present paper investigates the effect of a notch on the fatigue life of the hsla100 (­high strength low alloy) steel which is widely applicable in the marine industry. tensile test was conducted on specimens and mechanical properties were obtain...