Advanced, waveform based acoustic emission (AE) techniques have been successfully used to evaluate damage mechanisms in laboratory testing of composite coupons. An example is presented in which the initiation of transverse matrix cracking was monitored. In these tests, broad band, high fidelity acoustic sensors were used to detect signals which were then digitized and stored for analysis. Analy...

The dynamic stability of a composite plate with external electrorheological (ER) damper subjected to an axial periodic load is investigated. Electrorheological fluids are a class of smart materials, which exhibit reversible changes in mechanical properties when subjected to an electric field. As a result, the dynamic behavior of the structure is changed. The ER damper is used for suppressing th...

Purpose – The purpose of this work is to describe the effects of the length of cracks and the patch size on the stress intensity factors in a bonded composite repair structure containing multiple site damage. Design/methodology/approach – Finite element method was applied to simulate a bonded repair of a cracked aluminum plate with multiple site damage. A two-dimensional three-layer technique w...

friction stir processing was applied for fabricating an aluminum alloy based hybrid nano composite reinforced with nano sized al2o3 and micro sized graphite particles. a mixture of al2o3 and graphite particles was packed into a groove with 1 mm width and 4.5 mm depth, which had been cut in 5083 aluminum plate of 10 mm thick. packed groove was subjected to friction stir processing in order to im...

Plane strain transient finite thermomechanical deformations of heat-conducting functionally gradient materials comprised of tungsten and nickel–iron matrix are analyzed to delineate brittle/ductile failures by the nodal release technique. Each material is modeled as strain-hardening, strain-rate-hardening and thermally-softening. Effective properties are derived by the rule of mixtures. At nomi...

2014 Recent experiments have shown that interdigital transducers can couple strongly to plate modes in piezoelectric composite membranes. In this paper the dispersive properties and the piezoelectric coupling (039403BD/03BD) to these plate modes are presented The various types of modes are identified and related to crystalline symmetry. Results are given for stiffened-shear modes in zinc oxide ...

In this paper, the response of hybrid composite laminate plate reinforced by the smart wires (shape memory or the SMA wires) subjected to low velocity impact is studied. The smart wires are embedded within the layers of the composite laminate. The effect of the smart wires on contact force history, and deflection of these structures is investigated. The first-order shear deformation theory as w...

A repeated thermomechanical treatment (RTMT) was adopted to control the microstructure of a glass-balloon-dispersed aluminum alloy (AC3A) composite. The RTMT, which involves the repetition of a multi-step process and followed by heat treatment, was applied to a cast plate of the composite. The composite was successfully worked into a rod or sheet by either swaging or flat rolling. The porous gl...

BACKGROUND In the internal fixation of fractured bone by means of bone-plates fastened to the bone on its tensile surface, an on-going concern has been the excessive stress-shielding of the bone by the excessively-stiff stainless-steel plate. The compressive stress-shielding at the fracture-interface immediately after fracture-fixation delays callus formation and bone healing. Likewise, the ten...

The aim of this study is to compare the metallic and natural fiber reinforced polymer composite bone plates used in humerus fractures. A 3D finite element model was developed to analyze the performance of both types of plates. This study proposed on fabrication of natural fiber powdered material (like Sisal (Agave sisalana), Banana (Musa sapientum) and Roselle (Hibiscus sabdariffa)) Reinforced ...