Search results for "Tensile testing"
showing 10 items of 35 documents
Experimental studies on uniaxial and echibiaxial tensile tests applied to plastic materials sheets
2019
Abstract The main objective of this paper is to determine the behavior of few plastic materials using two different type of tests. We use classical uniaxial tensile test to determine the most important mechanical and elastic characteristics, such as: yield stress, Young modulus, tangent modulus, maximum stress and maximum strain and to plot engineering stress vs. engineering strain curve for these materials. The second test, that was used in this study, was echibiaxial tensile test on the spherical punch. This test was used to determine maximum breaking force and, of course maximum displacement of specimen on punch direction and others few important characteristics, such as: major and minor…
Effect of position and force tool control in friction stir welding of dissimilar aluminum-steel lap joints for automotive applications
2020
Widespread use of aluminum alloys for the fabrication of car body parts is conditional to the use of appropriate welding methods, especially if dissimilar welding must be performed with automotive steel grades. Friction stir welding (FSW) is considered to be a reasonable solution to obtain sound aluminum-steel joints. In this context, this work studies the effects of tool position and force control in dissimilar friction stir welding of AA6061 aluminum alloy on DC05 low carbon steel in lap joint configuration, also assessing proper welding parameter settings. Naked eye and scanning electron microscopy (SEM) have been used to detect macroscopic and microscopic defects in joints, as well as t…
In Vitro Measurement of Strain Localization Preceding Dissection of the Aortic Wall Subjected to Radial Tension
2020
AbstractBackgroundAortic dissection (AD) is a common pathology and challenging clinical problem. A better understanding of the biomechanical effects preceding its initiation is essential for predicting adverse events on a patient-specific basis. Moreover, the predictability of patient-specific biomechanics-based computational models is hampered by uncertainty about boundary conditions and material properties.ObjectivePredisposition of thoracic aortic aneurysms (TAA) to ADs can be related to the degradation of biomechanically important constituents in the aortic wall of TAAs. The goal of the present study is to develop a new methodology to measure strain fields in aortic tissues subjected to…
The Transverse Crack Tension test revisited
2016
Several problems arise when measuring the mode II interlaminar fracture toughness using a Transverse Crack Tension specimen; in particular, the fracture toughness depends on the geometry of the specimen and cannot be considered a material parameter. A preliminary experimental campaign was conducted on TCTs of different sizes but no fracture toughness was measured because the TCTs failed in an unacceptable way, invalidating the tests. A comprehensive numerical and experimental investigation is conducted to identify the main causes of this behaviour and a modification of the geometry of the specimen is proposed. It is believed that the obtained results represent a significant contribution in …
Microstructure and property of titanium heterogeneous laser welding
2015
International audience; Dissimilar welding has been investigated for three different couples of titanium alloys: α/α+β, α/β and α+ββp. Plates of 100 x 60 x 1.6 or 1.8 mm were welded with a Yb: YAG laser. Tensile tests show that the properties of the dissimilar welded specimens were generally controlled by Those of the weakest material except for the α+β/β where the ultimate tensile strength was approximately equal to the average value of both materials. In every case, the welding sample elongation was found to be smaller than that of the base metals. The rupture took place away from the bead and was found to be always located in the alloy having the lowest mechanical properties. Nevertheles…
Mechanical characterization of rose bengal and green light crosslinked collagen scaffolds for regenerative medicine
2021
Abstract Collagen is one of the most important biomaterials for tissue engineering approaches. Despite its excellent biocompatibility, it shows the non-negligible disadvantage of poor mechanical stability. Photochemical crosslinking with rose bengal and green light (RGX) is an appropriate method to improve this property. The development of collagen laminates is helpful for further adjustment of the mechanical properties as well as the controlled release of incorporated substances. In this study, we investigate the impact of crosslinking and layering of two different collagen scaffolds on the swelling behavior and mechanical behavior in micro tensile tests to obtain information on its wearin…
Induced Modification of Flexural Toughness of Natural Hydraulic Lime Based Mortars by Addition of Giant Reed Fibers
2020
Abstract Nowadays, there is a growing need to reduce the environmental impact generated by the use of inorganic materials for building applications. The aim of this work is to investigate the bio-lime based mortar flexural toughness improvement due to the addition of common reed fibers (Arundo donax L.) in order to evaluate their possible application as ductile eco-compatible prefabricated bricks or laying and joint mortars for masonry. Different sets of specimens were tested by varying the fiber weight content and the fiber length. Moreover, chemical treatments with Linseed Oil and Polyethylene glycol (PEG) were performed to improve the physical and mechanical properties of the fibers as w…
Prediction of Ductile Fractures in Metal-Forming Processes: an Approach Based on the Damage Mechanics
1994
The Authors propose a new approach for the prediction of ductile fractures in bulk metal forming processes: the approach is based on a numerical analysis able to take into account damage occurrence and evolution in constitutive equations. The model supplies the distribution of the void volume fraction in the workpiece during the deformation path: consequently, the comparison to a critical value, determined by means of a simple tension test, allows to predict the growth of defects. The proposed approach has been applied to the drawing process: the numerical results have been compared with a set of experimental tests showing a good predictive capability of the model.
Mechanical behaviour of natural cow leather in tension
2009
We study experimentally the microstructure and mechanical behavior of natural cow leather. Tensile tests are performed using leather strips to observe their deformation, creep and failure. It is found that the microstructure of cow leather is a layered, complicated network of fibers of different sizes from a few to a few hundreds of nanometers in diameter. They show nonlinear stress-strain relations and viscoelastic behavior. The effect of humidity is also examined. A simple theoretical model of a multilayered beam is proposed to describe the most basic behavior in tension.
Fatigue strength of a single lap joint SPR-bonded
2011
In the last years, hybrid joints, meaning with this the joints which consist in combining a traditional mechanical joint to a layer of adhesive, are gradually attracting the attention of various sectors of the construction of vehicles and transportation industries, for their better performance compared to just mechanical joints (self-piercing riveting SPR, riveting, and so on) or just to bonded joints. The paper investigates the fatigue behavior of a single lap joint self-piercing riveted (SPR) and bonded throughout fatigue tests. The considered geometric configuration allowed the use of two rivets placed longitudinally; an epoxy resin was used as adhesive. In the first part of the work sta…