1,720,984 research outputs found
Prediction of the tensile load-bearing capacity of a co-cured single lap joint considering residual thermal stresses
No full textIn this paper, stress distributions in a co-cured single lap joint subjected to a tensile load were investigated using the finite element analysis. Residual thermal stresses, which resulted from the curing process of the co-cured single lap joint, were also considered. Since the adhesive layer in the co-cured single lap joint was about 10 mum thick, very thin compared with the thickness of both adherends, the interface between the steel and composite adherends was assumed to be perfectly bonded. The co-cured single lap joint was analyzed with respect to several bond parameters such as the bond length and stacking sequence of the composite adherend. The failure mechanism of the co-cured single lap joint was partial cohesive failure in the composite material, which was significantly affected by the interfacial tensile stress at the free edge of the co-cured single lap joint. Interfacial tensile stress was a primary factor that caused interfacial delamination between the steel and composite adherends in the co-cured single lap joint. Finally, tensile load-bearing capacities calculated from the Ye-delamination failure criterion were compared with the experimental results, and relatively good agreement was found
Effects of bond parameters on fatigue characteristics of a cocured double lap joint subjected to cyclic tensile loads
No full textA cocured joint whose manufacturing process is simpler than that of an adhesively bonded joint is attractive for composite structures due to its several benefits. Fatigue behavior in the cocured joint is important because under alternating loads it will fail at stress levels much lower than it can withstand under monotonic loading. Although some researchers have recently reported on cocured joints, there are only a few articles published on the fatigue characteristics of cocured joints. In this article, effects of bond parameters on fatigue characteristics of a steel-composite cocured double lap joint under cyclic tensile loads were experimentally investigated. In order to observe stress distributions near the interface edge of the cocured double lap joint, finite element analysis was also performed. We considered the surface roughness of the steel adherend and the stacking sequence of the composite adherend as bond parameters. A fatigue failure mechanism of the cocured double lap joint was explained systematically by investigating the surfaces of failed specimens and stress distributions at the interface edge. Failure criteria of the cocured double lap joint under cyclic tensile loads were shown graphically
Bond parameters to improve tensile load bearing capacities of co-cured single and double lap joints with steel and carbon fiber-epoxy composite adherends
No full textA co-cured joining method has several advantages over an adhesively-bonded joining method for its simple manufacturing process. It requires neither an adhesive nor surface treatment of the composite adherend and uses excess resin to bond both adherends, including composite adherend. In this paper, the effects of bond parameters, including surface roughness on the steel adherend, stacking sequence of the composite adherend, and manufacturing pressure in the autoclave during the bonding process, on tensile load bearing capacities of plate-type co-cured single and double lap joints were investigated experimentally. Bond parameters were related to interfacial parameters such as a contact area and adhesive thickness, which affected the joint strength. Experimental results were explained with respect to all of interfacial parameters and bond parameters through investigating failure surfaces of the steel adherend and a lot of data of tensile load bearing capacities. In order to predict tensile load bearing capacities of co-cured single and double lap joints, we considered two different failure models using stress distributions in both co-cured lap joints obtained from finite element analysis. Finally, optimal conditions to improve the joint strength of co-cured single and double lap joints have been presented
The manufacturing process of co-cured single and double lap joints and evaluation of the load-bearing capacities of co-cured joints
No full textThe co-cured joining method, which is regarded as an adhesively bonded joining method, is an efficient joining technique because both the curing and joining process for the composite structures can be achieved simultaneously. In this paper, the manufacturing process of the co-cured joint was introduced and specimens of co-cured single and double lap joints of the plate type were fabricated and tested under a tensile load. The failure mechanism of co-cured single and double lap joints was discussed using stress distributions obtained from finite element analysis. Failure criteria of the co-cured single and double lap joints are proposed and verified by comparing the tensile load-bearing capacity calculated by failure criteria with tensile test results. (C) 2003 Elsevier Science B.V. All rights reserved
Review of simulation model for education of point-of-care ultrasound using easy-to-make tools
Full text linkPoint-of-care ultrasound (POCUS) is a powerful diagnostic tool and provides treatment guidelines in acute critical settings. However, the limitation of using POCUS is operator dependent. Appropriate and validated training for acquiring and using skills in practice must be conducted before using POCUS in clinical settings in order to keep patients safe. Simulation education models have been introduced as a way to solve and overcome these concerns. However, the commercial simulator with sufficiently secured fidelity is expensive and not always available. This review focused on the inexpensive and easily made simulators for education on POCUS in critical specific situations related to the airway, breathing, circulation, and disability. We introduced the simulators that used non-infectious materials, with easily transportable features, and that had a sonographic appearance reproducibility similar to human tissue. We also introduced the recipe of each simulator in two parts: Materials surrounding disease simulators (surrounding materials) and specific disease simulators themselves (target simulators). This review article covered the following: endotracheal or oesophageal intubation, lung (A-lines, B-lines, lung sliding, and pleural effusions such as hemothorax), central vein access, pericardial fluid (cardiac tamponade), the structure related to the eyes, soft tissue abscess, nerve (regional nerve block), and skull fracture simulators
Adhesively Bonded Lap-Joints for the Composite-Steel Shell Structure of High-Speed Vehicles
No full textA study on the lap shear strength of a co-cured single lap joint
No full textIn this paper, the lap shear strength of a co-cured single lap joint subjected to a tensile load was investigated by experimental analysis. Go-cured joint specimens with several different bonding parameters such as bond length, surface roughness, and stacking sequence of the composite laminate were fabricated and tested. The dependence of the lap shear strength of the co-cured joint on the bonding parameters was investigated from the experimental results. The failure mechanism of the co-cured single lap joint was partially cohesive failure. The lap shear strength of the co-cured single lap joint was significantly affected by the bond length and the stacking sequence of the composite laminate. However. the effect of surface roughness on the lap shear strength of the co-cured single lap joint was not so significant
Axial crush and bending collapse of a aluminum/GFRP hybrid square tube and its energy absorption capability
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
