Buckling of symmetrical circular sandwich plates with variable mechanical properties of the core in the radial direction

The influence of Ti oxide on the toughness of heat affected zone for low carbon bainitic steels has been investigated. The optical microscope, SEM and TEM were used to analyze the composition, size and distribution of the inclusions, and the microstructure and mechanical properties after welding thermal simulation were also investigated. The effect of Ti oxide inclusion on the transformation of acicular ferrite has also been studied. The results show that after the melting with Ti dioxide technique the inclusion is complex, in the core is Ti oxides about 1-3 micron and around it is MnS. It has been found the acicular ferrite can nucleate at the inclusions and the Ti oxide inclusion will promote the nucleation of acicular ferrite, and the acicular ferrite will block the growth of bainite. Therefore by introducing the Ti oxide in the steels the microstructure of HAZ could be refined markedly therefore the toughness of HAZ can be improved evidently.

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LUCEFIN C20

Alloy Digest ◽

10.31399/asm.ad.cs0209 ◽

2021 ◽

Vol 70 (3) ◽

Keyword(s):

Mechanical Properties ◽

Physical Properties ◽

Tensile Properties ◽

Alloy Steel ◽

Heat Treating ◽

Low Carbon ◽

Wear Resistant ◽

The Core

Abstract Lucefin C20 is a low-carbon, non-alloy steel that is used in the normalized, cold finished, or quenched and tempered condition. It may also be used in the carburized or carbonitrided, and subsequently quench hardened and tempered, condition for parts requiring a hard wear-resistant surface, but with little need for increased mechanical properties in the core. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: CS-209. Producer or source: Lucefin S.p.A..

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Calculating Mechanics Characteristics of Single-Walled Carbon Nanotube Materials by Finite Element Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.730.548 ◽

2017 ◽

Vol 730 ◽

pp. 548-553

Author(s):

Jing Ge ◽

Hao Jiang ◽

Zhen Yu Sun ◽

Guo Jun Yu ◽

Bo Su ◽

...

Keyword(s):

Mechanical Properties ◽

Finite Element ◽

Radial Direction ◽

Element Model ◽

Beam Element ◽

Beam Position ◽

Single Walled Carbon ◽

Finite Element Software ◽

Calculation Results ◽

The Moment

In this paper, we establish the mechanical property analysis of Single-walled Carbon Nanotubes (SWCNTs) modified beam element model based on the molecular structural mechanics method. Then we study the mechanical properties of their radial direction characteristics using the finite element software Abaqus. The model simulated the different bending stiffness with rectangular section beam elements C-C chemical force field. When the graphene curled into arbitrary chirality of SWCNTs spatial structure, the adjacent beam position will change the moment of inertia of the section of the beam. Compared with the original beam element model and the calculation results, we found that the established model largely reduced the overestimate of the original model of mechanical properties on the radial direction of the SWCNTs. At the same time, compared with other methods available in the literature results and the experimental data, the results can be in good agreement.

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Application of the nanoindentation method in assessing of properties of cement composites modified with silica-magnetite nanostructures

MATEC Web of Conferences ◽

10.1051/matecconf/201816302002 ◽

2018 ◽

Vol 163 ◽

pp. 02002 ◽

Cited By ~ 1

Author(s):

Elzbieta Horszczaruk ◽

Roman Jedrzejewski ◽

Jolanta Baranowska ◽

Ewa Mijowska

Keyword(s):

Mechanical Properties ◽

Magnetite Nanoparticles ◽

Positive Influence ◽

Cement Matrix ◽

Core Shell ◽

Indentation Modulus ◽

Cement Composites ◽

Interfacial Zone ◽

Berkovich Indenter ◽

The Core

The results of investigation of the cement composites modified with 5% of silica-magnetite nanostructures of the core-shell type are presented in the paper. The nanoindentation method employing three-sided pyramidal Berkovich indenter was used in the research. The mechanical properties and microstructure of the modified cement composites were evaluated on the basis of the values of hardness and indentation modulus measured inside the cement matrix and in the aggregate-paste interfacial zone. The results were compared with those obtained for the reference composites without nanostructures. The positive influence of the presence of silica-magnetite nanoparticles on the tested properties was found out.

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Moisture Absorption Effects on the Mechanical Properties of Sandwich Biocomposites with Cork Core and Flax/PLA Face Sheets

Molecules ◽

10.3390/molecules26237295 ◽

2021 ◽

Vol 26 (23) ◽

pp. 7295

Author(s):

Hom Nath Dhakal ◽

Chulin Jiang ◽

Moumita Sit ◽

Zhongyi Zhang ◽

Moussa Khalfallah ◽

...

Keyword(s):

Mechanical Properties ◽

Failure Modes ◽

Moisture Absorption ◽

Mechanical Performance ◽

Core Sample ◽

Environmental Benefits ◽

Matrix Cracking ◽

Core Material ◽

Poly Lactic Acid ◽

The Core

The aim of this study was to evaluate the moisture absorption behaviour and its influence on the mechanical properties of newly developed sandwich biocomposites with flax fibre-reinforced poly-lactic acid (PLA) face sheets and soft cork as the core material. Three different types of sandwich biocomposite laminates comprised of different layup configurations, namely, non-woven flax/PLA (Sample A), non-woven flax/PLA and cork as core (Sample B) and non-woven flax/paper backing/PLA, cork as core (Sample C), were fabricated. In order to evaluate the influence of moisture ingress on the mechanical properties, the biocomposites were immersed in seawater for a period of 1200 h. The biocomposites (both dry and water immersed) were then subjected to tensile, flexural and low-velocity falling weight impact tests. It was observed from the experimental results that the moisture uptake significantly influenced the mechanical properties of the biocomposites. The presence of the cork and paper in sample C made it more susceptible to water absorption, reaching a value of 34.33%. The presence of cork in the core also has a considerable effect on the mechanical, as well as energy dissipation, behaviours. The results of sample A exhibited improved mechanical performance in both dry and wet conditions compared to samples B and C. Sample A exhibits 32.6% more tensile strength and 81.4% more flexural strength in dry conditions than that in sample C. The scanning electron microscopy (SEM) and X-ray micro-CT images revealed that the failure modes observed are a combination of matrix cracking, core crushing and face core debonding. The results from this study suggest that flax/PLA sandwich biocomposites can be used in various lightweight applications with improved environmental benefits.

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Study on the Effect of High-Temperature Heat Treatment on the Microscopic Pore Structure and Mechanical Properties of Tight Sandstone

Geofluids ◽

10.1155/2021/8886186 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Liangbin Dou ◽

Guanli Shu ◽

Hui Gao ◽

Jinqing Bao ◽

Rui Wang

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Pore Structure ◽

Water Cooling ◽

Tight Sandstone ◽

The Core ◽

Core Samples ◽

High Temperature Heat Treatment ◽

Different Temperatures ◽

Cooling Methods

The investigation of changes in physical properties, mechanical properties, and microscopic pore structure characteristics of tight sandstone after high-temperature heat treatment provides a theoretical basis for plugging removal and stimulation techniques, such as high energy gas fracturing and explosive fracturing. In this study, core samples, taken from tight sandstone reservoirs of the Yanchang Formation in the Ordos Basin, were first heated to different temperatures (25-800°C) and then cooled separately by two distinct cooling methods—synthetic formation water cooling and natural cooling. The variations of wave velocity, permeability, tensile strength, uniaxial compressive strength, and microscopic pore structure of the core samples were analyzed. Experimental results demonstrate that, with the rise of heat treatment temperature, the wave velocity and tensile strength of tight sandstone decrease nonlinearly, yet its permeability increases nonlinearly. The tight sandstone’s peak strength and elastic modulus exhibit a trend of the first climbing and then declining sharply with increasing temperature. After being treated by heat at different temperatures, the number of small pores varies little, but the number of large pores increases obviously. Compared to natural cooling, the values of physical and mechanical properties of core samples treated by synthetic formation water cooling are apparently smaller, whereas the size and number of pores are greater. It can be explained that water cooling brings about a dramatic reduction of tight sandstone’s surface temperature, generating additional thermal stress and intensifying internal damage to the core. For different cooling methods, the higher the core temperature before cooling, the greater the thermal stress and the degree of damage caused during the cooling process. By taking into consideration of changes in physical properties, mechanical properties, and microscopic pore structure characteristics, the threshold temperature of tight sandstone is estimated in the range of 400-600°C.

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COMPUTER SIMULATION OF BENDING CIRCULAR SANDWICH PLATES USING ANALYTICAL AND NUMERICAL APPROACHES

Radio Electronics Computer Science Control ◽

10.15588/1607-3274-2014-1-11 ◽

2014 ◽

Vol 0 (1) ◽

Cited By ~ 1

Author(s):

A. V. Kudin ◽

S. V. Choporov

Keyword(s):

Computer Simulation ◽

Sandwich Plates ◽

Circular Sandwich Plates ◽

Numerical Approaches

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Free Vibration of Sandwich Plates and Shells by Using Zig-Zag Function

Shock and Vibration ◽

10.1155/2009/573674 ◽

2009 ◽

Vol 16 (5) ◽

pp. 495-503 ◽

Cited By ~ 19

Author(s):

S. Brischetto ◽

E. Carrera ◽

L. Demasi

Keyword(s):

Free Vibration ◽

Free Vibration Analysis ◽

Sandwich Plates ◽

Vibration Modes ◽

Fundamental Vibration ◽

First Derivative ◽

The Core ◽

Sandwich Plates And Shells ◽

Plates And Shells ◽

Free Vibration Response

This paper analyses the free vibration response of sandwich curved and flat panels by introducing the zig-zag function (—1)kζk(ZZF) in the displacement models of classical and higher order two-dimensional shell theories. The main advantage of ZZF is the introduction of a discontinuity in the first derivative, zig-zag effect, of the displacements distribution with correspondence to the core/faces interfaces. Results including and discarding ZZF are compared. Several values of face-to-core stiffness ratio (FCSR) and geometrical plate/shell parameters have been analyzed. Both fundamental vibration modes and those corresponding to high wave numbers are considered in the analysis. It is concluded that: (1) ZZF is highly recommended in the free vibration analysis of sandwich plates and shells; (2) the use of ZZF makes the error almost independent by FCSR parameter; (3) ZZF is easy to implement and its use should be preferred with respect to other `more cumbersome' refined theories.

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Circular Sandwich Plates Under Eccentric Load

Journal of the Engineering Mechanics Division ◽

10.1061/jmcea3.0001080 ◽

1969 ◽

Vol 95 (1) ◽

pp. 235-246 ◽

Cited By ~ 2

Author(s):

Jao-Shiun Kao

Keyword(s):

Sandwich Plates ◽

Eccentric Load ◽

Circular Sandwich Plates

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An attempt to use „Tetra Pak” waste material in particleboard technology

Annals of WULS, Forestry and Wood Technology ◽

10.5604/01.3001.0015.2376 ◽

2021 ◽

Vol 114 ◽

pp. 70-75

Author(s):

Radosław Auriga ◽

Piotr Borysiuk ◽

Alicja Auriga

Keyword(s):

Mechanical Properties ◽

Water Absorption ◽

Bending Strength ◽

Physical And Mechanical Properties ◽

Core Layer ◽

Waste Material ◽

Thickness Swelling ◽

The Core ◽

Tetra Pak ◽

The Impact

An attempt to use „Tetra Pak” waste material in particleboard technology. The study investigates the effect of addition Tetra Pak waste material in the core layer on physical and mechanical properties of chipboard. Three-layer chipboards with a thickness of 16 mm and a density of 650 kg / m3 were manufactured. The share of Tetra Pak waste material in the boards was varied: 0%, 5%, 10% and 25%. The density profile was measured to determine the impact of Tetra Pak share on the density distribution. In addition, the manufactured boards were tested for strength (MOR, MOE, IB), thickness swelling and water absorption after immersion in water for 2 and 24 hours. The tests revealed that Tetra Pak share does not affect significantly the value of static bending strength and modulus of elasticity of the chipboard, but it significantly decreases IB. Also, it has been found that Tetra Pak insignificantly decreases the value of swelling and water absorption of the chipboards.

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