Structure heterogeneity and mechanical properties studied in thickness up to 100 mm of low-alloyed shipbuilding steel sheets with a yield strength not less than 420 MPa

This paper presents a study of changes in the structure and properties in thickness of rolled sheets up to 100 mm of low-alloyed shipbuilding steel with a yield point not less than 420 MPa. The fracture surface of samples after impact bending tests at low temperatures was investigated. It was found that the combination of the parameters of lath morphology bainite (fraction, areas average size and length) and the size of structural elements at given tolerance angles of 5 and 15° (indicating the presence or absence of a developed subgrain structure of deformation origin) determine the level of impact work at low temperatures testing.

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Research of the cold resistance of metals by indentation with registration of an acoustic emission signal

10.36652/0042-4633-2020-8-61-64 ◽

2020 ◽

pp. 61-64

Author(s):

Yu.G. Kabaldin ◽

A.A. Khlybov ◽

M.S. Anosov ◽

D.A. Shatagin

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Acoustic Emission ◽

Acoustic Emission Signal ◽

Low Temperatures ◽

Cold Resistance ◽

Emission Signal ◽

Impact Bending ◽

Artificial Neural

The study of metals in impact bending and indentation is considered. A bench is developed for assessing the character of failure on the example of 45 steel at low temperatures using the classification of acoustic emission signal pulses and a trained artificial neural network. The results of fractographic studies of samples on impact bending correlate well with the results of pulse recognition in the acoustic emission signal. Keywords acoustic emission, classification, artificial neural network, low temperature, character of failure, hardness. [email protected]

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Springback evaluation for TRIP 800 steel sheets by simple bending tests

10.1063/1.4707560 ◽

2012 ◽

Cited By ~ 2

Author(s):

F. J. Avellaneda ◽

V. Miguel ◽

J. Coello ◽

A. Martínez ◽

A. Calatayud

Keyword(s):

Bending Tests ◽

Steel Sheets

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The Spread of Corrosion in Cast Iron and its Effect on the Life Cycle of Transportation Vehicles

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201765020383 ◽

2017 ◽

Vol 65 (2) ◽

pp. 383-389 ◽

Cited By ~ 1

Author(s):

Tomáš Binar ◽

Jiří Švarc ◽

Petr Dostál ◽

Michal Šustr ◽

Jan Tippner

Keyword(s):

Impact Strength ◽

Fractographic Analysis ◽

Bending Test ◽

Material Surface ◽

Bending Tests ◽

Corrosion Tests ◽

Fracture Surfaces ◽

Impact Bending ◽

Notch Impact Strength ◽

The Impact

This article deals with the spread of corrosion in material at different exposure times, and its effect on the measured brittle fracture and notch impact strength under different temperature conditions. To assess the degradational effect of corrosion on the material characteristics represented by the measured impact strength, we conducted a fractographic analysis of fracture surfaces, the aim of which was to evaluate the spread of corrosion in the material. In the first part of the experiment, two corrosion tests are simulated with a duration time of 432 and 648 hours, to compare the degradation effect of corrosion on the notch impact strength, depending on the duration of the corrosion tests. The following part shows the results of the impact bending test, where the experiment was conducted in an area of reduced and increased temperatures. The final part summarizes the results of the fractographic analysis of sample fracture surfaces from the impact bending tests. Based on the measured the length of the corrosion cracks, we analyzed the sample at the notch and from the material surface after the impact bending test.

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Use of Fine-Grained Heat-Strengthened Steels to Increase the Operation Qualities of Bunker Capacities from Thin-Walled Galvanized Profiles

Science and Transport Progress Bulletin of Dnipropetrovsk National University of Railway Transport ◽

10.15802/stp2021/227198 ◽

2021 ◽

pp. 84-93

Author(s):

Y. I. Hezentsvei ◽

D. O. Bannikov

Keyword(s):

Low Temperatures ◽

High Strength Steels ◽

High Strength ◽

Numerical Calculations ◽

Structural Scheme ◽

Plan View ◽

Fine Grained ◽

Steel Sheets ◽

Stiffening Ribs ◽

Corrugated Sheets

Purpose. The work is aimed to study the use efficiency of fine-grained heat-strengthened steels (mainly 10G2FB) for steel bunker capacities. At the same time, the structural scheme of such a structure using corrugated steel sheets is considered as the main variant. Methodology. To achieve this purpose, a series of numerical calculations was carried out for a steel bunker capacity of a pyramidal-prismatic type with overall dimensions in plan view of 6×5.2 m and a total height of 4.5 m. The capacity was designed for complicated working conditions, in particular, increased loads, including long-term dynamic ones. The potential possibility of operating the container under conditions of high or low temperatures was also taken into account. At the same time, both the traditional structural scheme of a bunker capacity with horizontal stiffening ribs and the developed structural scheme based on corrugated steel sheets were analyzed. The calculations were carried out by the finite element method based on the SCAD for Windows project complex. Findings. Based on the results of the analysis and comparison of the data obtained in numerical calculations, it was found that the use of fine-grained heat-strengthened high-strength steels (for example, steel 10G2FB) for bunker capacities, both the traditional structural scheme with stiffening ribs and the developed structural scheme based on corrugated sheets, allows reducing material consumption by about 30% in both cases. At the same time, due to the good performance of fine-grained heat-strengthened steel 10G2FB, both at high and at low temperatures, it can be effectively used for steel bunker capacities that work in difficult conditions. Originality. The possibility and efficiency of the use of fine-grained, heat-strengthened high-strength steels for the construction of a steel bunker capacity is estimated. At the same time, such an estimation was given not only for structures of the traditional structural scheme with horizontal stiffening ribs, but also for bunkers with a developed structural scheme based on corrugated sheets. Practical value. From a practical point of view, quantitative parameters of the stress-strain state were obtained during investigations of various design variants for a steel bunker capacity. The data are presented in a compact form that is easy to evaluate and compare. They allow us to state about the improvement of the operation characteristics of capacities and the potential reduction of the risks of their failures and accidents during operation.

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Comparação entre a eficiência estrutural de perfis soldados de aço e perfis de aço formados a frio

REEC - Revista Eletrônica de Engenharia Civil ◽

10.5216/reec.v12i3.39300 ◽

2016 ◽

Vol 12 (3) ◽

Author(s):

Uiatan Aguiar Nogueira ◽

Matilde Batista Melo ◽

Daniel De Lima Araujo

Keyword(s):

Bending Strength ◽

Steel Beams ◽

Steel Beam ◽

Structural Elements ◽

Structural System ◽

Welded Steel ◽

Bending Tests ◽

Structural Efficiency ◽

Cold Formed Steel

RESUMO: A Análise de elementos estruturais, realizadas durante as etapas de projeto de uma estrutura, é parte fundamental para garantia de bom desempenho e estabilidade do sistema estrutural. Na execução de algumas estruturas, como as coberturas em edificações, é usual o emprego de perfis leves de aço formados a frio devido ao seu baixo peso. Esta pesquisa tem por objetivo avaliar a eficiência estrutural desses perfis quando comparados, por exemplo, aos perfis soldados compactos. Para tanto, foram realizados ensaios de flexão em quatro vigas biapoiadas submetidas a duas forças concentradas, de forma a se obter flexão pura no meio do vão das vigas. Estas foram instrumentadas para a determinação da sua rigidez e da sua resistência à flexão. A principal contribuição deste trabalho é demonstrar a eficiência estrutural de perfis formados a frio em seção caixa submetidos à flexão em comparação com perfis de seção tipo “H” soldados. ABSTRACT: The analysis of structural elements, in a structure’s design, is an essential step to ensure good performance and stability of the structural system. In any types of structures, such as roofing in buildings, it’s usual using cold-formed steel beams due to their small weight. This research seeks to evaluate the structural efficiency of cold-formed steel beams when compared, for example, to compact welded steel beams. Thus, bending tests were performed in four simply supported beams submitted to two concentrated loads, in order to obtain pure flexure at the mid-span of the beams. These beams were instrumented for the determination of their rigidity and bending strength. The results showed that the cold-formed steel beam, box-shaped, presented structural efficiency similar to the welded steel beam “H” shaped.

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Non-Destructive Tests and Bending Tests on Chestnut Structural Timber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.778.167 ◽

2013 ◽

Vol 778 ◽

pp. 167-174 ◽

Cited By ~ 3

Author(s):

Beatrice Faggiano ◽

Maria Rosaria Grippa ◽

Bruno Calderoni

Keyword(s):

Research Study ◽

Timber Structures ◽

Structural Elements ◽

Bending Tests ◽

Experimental Activity ◽

Collapse Mechanisms ◽

Regression Approach ◽

Non Destructive ◽

Non Destructive Techniques

In the context of a more wide research study for in situ mechanical identification of ancient timber structures by non-destructive techniques, the paper illustrates the experimental activity developed on structural elements made of old chestnut timber, 4x4x76 cm size: 24 squared specimens were extracted by six elements in actual dimensions, already used in a previous tests campaign. Non-destructive (ND: hygrometric, sclerometric and resistographic) and destructive (D: bending) tests were performed, the latter according to UNI EN 408 (2004) standard, in order to assess the mechanical properties and the collapse mechanisms of chestnut timber. Data gathered are presented in detail and, NDT-DT correlations, obtained through a linear regression approach, are provided to predict wood density, strength and modulus of elasticity of the tested members.

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The Effect of High Strain Rate on Properties and Microstructure of the Fully Austenitic High Mn Steel

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.246.55 ◽

2016 ◽

Vol 246 ◽

pp. 55-58 ◽

Cited By ~ 1

Author(s):

Anna Śmiglewicz ◽

Magdalena Jabłońska ◽

Adam Płachta ◽

Kinga Rodak ◽

Rafał Michalik

Keyword(s):

High Strain Rate ◽

Strain Rate ◽

High Strain ◽

Impact Resistance ◽

Break Point ◽

Mechanical Twinning ◽

Manganese Steel ◽

Structural Investigations ◽

Bending Tests ◽

Impact Bending

In the paper, results of impact bending tests of a high-manganese steel of X30MnAlSi26-4-3 grade are presented. The tests were carried out using a flywheel machine, suitable for dynamic tensile tests and impact bending tests in the range of linear velocity of the forcing element from 5 ÷ 40 m/s. The obtained test results were compared with the results of impact resistance of the studied steel determined using Charpy machine. Structural investigations were carried out using light microscope and scanning transmission electron microscopy. Creating a mechanical twins at different strain rates was analyzed. The surfaces of fractures formed in the break point during bending tests were analyzed, and they indicate a presence of mixed transcrystalline fractures with a predominance of plastic fractures. Substructure studies revealed the presence of mechanical twinning induced in a high strain rate for the X30MnAlSi26-4-3 steel.

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STRUCTURAL AND PHASE TRANSFORMATIONS IN THE FeO-SiO2 CaO-FeO I SYSTEM AT INFLUENCE OF HIGH TEMPERATURES

Bulletin of Belgorod State Technological University named after V G Shukhov ◽

10.12737/22714 ◽

2016 ◽

Vol 1 (12) ◽

pp. 165-169

Author(s):

Ястребинский ◽

Roman Yastrebinskiy ◽

Павленко ◽

Zoya Pavlenko

Keyword(s):

Phase Transformations ◽

Low Temperatures ◽

Amorphous Structure ◽

Structural Elements ◽

Temperature Influence ◽

Continuous Change ◽

Structural And Phase Transformations ◽

Two Component ◽

Main Components ◽

Ionic Lattice

In work structural and phase transformations in two-component the iron oxides systems are considered at high-temperature influence, on the example of bivalent oxide of iron and oxides of calcium and silicon, by the being one of the main components of cement binding. Taking into account structure of a radiation protective composite ratios of FeO:CaO =2:1 and FeO:SiO2=4:1 are considered. Heat treatment of the FeO:CaO system in the recovery environment intensified dissociation of calcite and displaced her to the low temperatures area (from 700-1000 °C in the oxidizing environment to 600–800 °C) that is caused by influence of iron of various valency (first of all magnetite) on an ionic lattice of calcite. At 600 °C there is a formation of monocalcic ferrite. In process of enrichment of the СаО system in the range of 700–800 °C monocalcic ferrite passed into two-calcic. Formation of ferrite happens at continuous change of a valent and coordination condition of ions of iron and degree of an ionnost and covalence of a chemical bond of Fe-O in ferriferous complexes. In the FeO-SiO2 system it is established: modification transition of quartz in kristobalit began at 800 °C and intensively develops at 900 °C, against 1200 °C in oxidizing conditions; to modification transition of quartz in kristobalit formation of silicon dioxide with partially amorphous structure in the range of 600–700 °C consisting of ring structural elements from [SiO4] - tetrahedrons preceded.

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