The purpose of this study was to compare the polymerization shrinkage stress of composite resins (microfilled, microhybrid and hybrid) photoactivated by quartz-tungsten halogen light (QTH) and light-emitting diode (LED). Glass rods (5.0 mm x 5.0 cm) were fabricated and had one of the surfaces air-abraded with aluminum oxide and coated with a layer of an adhesive system, which was photoactivated...

This paper focused on numerical study of hybrid composite specimens, which was experimentally done by preparing according to ASTM standards. Hybrid Composites are the formed by the combination of more than one reinforcement and matrix, which exibits very good properties compared to that of single reinforcement composites. These materials shows better flexibility when comparing with other compos...

In this assessment, hybrid composites were prepared from the combination of industrial waste, as marble waste powder (MWP) with conventional fillers, carbon black (CB) as well as silica as reinforcing material, incorporated with natural rubber (NR). The properties studied were curing, mechanical and swelling behavior. Assimilation of CB as well as silica into MWP containing NR compound responde...

Aluminium matrix composites with alumina reinforcements give superior mechanical & physical properties. Their applications in several fields like automobile, aerospace, defense, sports, electronics, bio-medical and other industrial purposes are becoming essential for the last several decades. In the present work, fabrication of hybrid composite was done by Stir casting technique using Al 6061 a...

The flexural fatigue behavior of hybrid composite rods comprised of unidirectional carbon and glass fibers was investigated. Damage was evaluated by monitoring stiffness loss as a function of cycles, and bending fatigue failure was defined in terms of strength retention. The acoustic emission technique and microscopic examination were used to characterize damage progression and failure mechanis...

This article examines the role of similarity in the hybridization of concepts, focusing on hybrid products as an applied test case. Hybrid concepts found in natural language, such as singer songwriter, typically combine similar concepts, whereas dissimilar concepts rarely form hybrids. The hybridization of dissimilar concepts in products such as jogging shoe mp3 player and refrigerator TV thus ...

Designing a hybrid course entails the challenge of choosing learning activities for each of the face-toface and online environments--and sequencing and coordinating the activities across the two environments--to promote student attainment of the course’s learning objectives. This paper presents a study comparing student performance in an undergraduate Principles of Microeconomics course taught ...

Hole drilling operations are common in fibre reinforced plastics FRP’s to facilitate fastener assembly to other parts in more complex structures. As these materials are non-homogeneous, drilling causes some damages, like delamination, for example. Delamination can be reduced by a careful selection of drilling parameters, drill material and drill bit geometry. In this work two types of laminates...

The use of natural fiber reinforced composites has continuously increased during recent years due to their low density, low cost and environmental friendliness. At current study, a preliminary investigation on the impact properties and morphologies of unsaturated polyester reinforced by jute woven fabric from the used coffee bags with different moisture contents were carried out. Additionally, ...