Search results for "Tensile test"

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…

A practical approach to estimate the degree of binder activity of reclaimed asphalt materials

2019

Using Reclaimed Asphalt (RA) in new asphalt mixtures can reduce the amount of new material required thereby saving money and natural resources. In addition, asphalt mixtures with RA have shown comparable properties and performance to that generally associated with asphalt mixtures made with 100% virgin material. However, RA content in pavement surface layers is still limited due to specification and technical limitations. For higher contents, the aged RA binder must be analysed to accurately determine the requirements for virgin binders and additives while the degree of blending (DOB) between the RA binder and the virgin binder also needs to be quantified. This is not a simple process and g…

Biomechanical study on ascending aortic aneurysms associated with quadricuspid aortic valve

2020

The quadricuspid aortic valve (QAV) is a rare anatomical situation and the biomechanical properties are not well known when it is associated with ascending aortic aneurysms (AsAA). The objective is to find out what is the biomechanical properties in such situation and to compare it with the existing data. In a sixty-three-years-old female (BMI 26,4) with hypertension disease, QAV, AsAA of 52 mm, an aortic valve and ascending aorta replacement were performed. The aortic wall sample was collected within 30 mins after replacement, partitioned related to medial, posterior, lateral, and anterior quadrants. The sample was cut in square size (15 mm × 15 mm, n = 13) with marking the circumferential…

Mechanical Characterization of a Basalt Fabric for TRM Composites: Role of the Test Variables

2021

Textile reinforced mortar (TRM) materials are currently receiving great attention for the strengthening of reinforced concrete and masonry structural elements. Mortars with different strength classes have been coupled with different kind of synthetic fabrics, such as carbon, glass, steel, PBO. Recently natural fibres and, in particular, basalt fibres are receiving increasing interest since they proved to be a promising alternative to the most common synthetic fabrics, thanks to the reduced production costs and the consequent benefits in terms of environmental impact. This paper presents an experimental investigation comprising forty-one monotonic tensile tests on textile strips made with a …

New Lignocellulosic Aristida adscensionis Fibers as Novel Reinforcement for Composite Materials: Extraction, Characterization and Weibull Distributio…

2019

In this research, the Aristida adscensionis fibers (AAFs) were taken out from the plants and its fundamental properties anlayzed for the first time. The AAFs were characterized and compared with other natural fibers by the use of physico-chemical analysis and various characterization techniques such as FT-IR, XRD, NMR, TGA, SEM and AFM. Chemical analysis showed that A. adscensionis fibers have a high cellulose content of 70.78% whereas the contents of lignin and wax are equal to 8.91% and 2.26%, respectively. The FT-IR, XRD and NMR analysis confirmed that AAFs are rich in cellulose content with CI and CS equal to 58.9% and 11.5 nm, respectively. Pycnometer analysis allowed to estimate a den…

Experimental investigation on the effectiveness of basalt-fibre strengthening systems for confining masonry elements

L’impiego di materiali compositi per il rinforzo di colonne in muratura è diventato una pratica ampiamente diffusa nel corso degli ultimi decenni. Questa tecnica, che consiste generalmente nell’applicazione di materiali polimerici fibrorinforzati (Fibre Reinforced Polymer-FRP), ha mostrato buone potenzialità, essendo in grado di garantire notevoli incrementi di resistenza e duttilità dell’elemento rinforzato, grazie ad un’azione di confinamento passivo. Tuttavia, l’impiego di compositi a matrice polimerica presenta alcuni limiti legati soprattutto alle prestazioni delle resine epossidiche, che a causa della loro natura sintetica danno luogo a problemi di compatibilità con il supporto murari…

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…

Experimental application of digital image correlation for the tensile characterization of basalt FRCM composites

2021

Abstract Composites made with inorganic matrix, namely fabric reinforced cementitious mortar (FRCM) composites are becoming widespread as strengthening materials for existing masonry structures. These composites are made of a dry grid of fibres embedded in an inorganic matrix. FRCMs can be considered a valid alternative to traditional organic composites such as fibre reinforced polymers (FRPs) because of their better compatibility with the masonry support. This work presents an experimental study for the tensile characterization of a basalt fabric reinforced cementitious mortar (BFRCM) composite. Tensile tests were carried out on coupons reinforced with one, two or three layers of grid to i…

KNOWN RESIDUAL STRESS SPECIMENS USING OPPOSED INDENTATION

2009

In order to test new theories for residual stress measurement or to test the effects of residual stress on fatigue, fracture, and stress corrosion cracking, a known stress test specimen was designed and then fabricated, modeled, and experimentally validated. To provide a unique biaxial stress state, a 60 mm diameter 10 mm thick disk of 316L stainless steel was plastically compressed through the thickness with an opposing 15 mm diameter hard steel indenters in the center of the disk. For validation, the stresses in the specimen were first mapped using time-of-flight neutron diffraction and Rietveld full pattern analysis. Next, the hoop stresses were mapped on a cross section of two disks usi…