scholarly journals Mechanical Testing of Recycled HDPE Extruded Hollow Section

2020 ◽  
Vol 4 (2) ◽  
pp. 112-121
Author(s):  
Greg Wheatley ◽  
Rendage Sachini Sandeepa Chandrasiri
Keyword(s):  
Thermal Expansion ◽  
Yield Strength ◽  
Ultimate Strength ◽  
Modulus Of Elasticity ◽  
Coefficient Of Thermal Expansion ◽  
Linear Thermal Expansion ◽  
Environmental Benefits ◽  
Hollow Section ◽  
Significant Difference ◽  
Recycled Hdpe

High density polyethylene (HDPE) is a thermoplastic polymer which is classified as one of the highly consumed types of plastics. One major advantage of thermoplastic materials is their ability of recycling and reprocessing which will bring considerable economicand environmental benefits. The present paper, therefore, endeavours to explore the practical possibility of using recycled HDPE hollow section as a replacement of virgin HDPE made by the extrusion process. The main focus of the study was to evaluate the mechanical performance of the recycled HDPE and compare the results with virgin or non-recycled HDPE.  The modulus of elasticity, tensile yield and ultimate strength, compressive yield and ultimate strength, flexural yield and ultimate strength and the coefficient of thermal expansion were the main parameters to be checked against the respective mechanical properties. Thus, pursuant to the rsults, it was found out  that the modulus of elasticity and the tensile yield strength are lower in recycled HDPE compared to the non-recycled HDPE. However, there is no significant difference between the recycled and non-recycled HDPE for the tensile ultimate strength, compressive yield strength and compressive ultimate strength. The flexural yield strength and flexural ultimate strength properties of the recycled HDPE proved to be superior to those of the non-recycled HDPE. The coefficient of linear thermal expansion of the recycled HDPE sample was 130 μm/(m.°C) and that for the non-recycled HDPE was 142 μm/(m.°C).

scholarly journals Improving Mechanical, Thermal and Damping Properties of NiTi (Nitinol) Reinforced Aluminum Nanocomposites

2020 ◽  
Vol 4 (1) ◽  
pp. 19 ◽  
Author(s):  
Penchal Reddy Matli ◽  
Vyasaraj Manakari ◽  
Gururaj Parande ◽  
Manohar Reddy Mattli ◽  
Rana Abdul Shakoor ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Thermal Expansion ◽  
Elastic Modulus ◽  
Yield Strength ◽  
Coefficient Of Thermal Expansion ◽  
Microwave Sintering ◽  
Hot Extrusion ◽  
Damping Capacity ◽  
Damping Properties ◽  
Niti Particle

In the present study, Ni50Ti50 (NiTi) particle reinforced aluminum nanocomposites were fabricated using microwave sintering and subsequently hot extrusion. The effect of NiTi (0, 0.5, 1.0, and 1.5 vol %) content on the microstructural, mechanical, thermal, and damping properties of the extruded Al-NiTi nanocomposites was studied. Compared to the unreinforced aluminum, hardness, ultimate compression/tensile strength and yield strength increased by 105%, 46%, 45%, and 41% while elongation and coefficient of thermal expansion (CTE) decreased by 49% and 22%, respectively. The fabricated Al-1.5 NiTi nanocomposite exhibited significantly higher damping capacity (3.23 × 10−4) and elastic modulus (78.48 ± 0.008 GPa) when compared to pure Al.

Tangguh LNG Project Statistical Young’s Modulus and Thermal Expansion Coefficient Testing of Clad Pipe Specimens

2011 ◽  
Author(s):  
Terry Griffiths ◽  
Isabel Hadley ◽  
Richard Johnson ◽  
Fabio Micari
Keyword(s):  
Thermal Expansion ◽  
Young’S Modulus ◽  
Room Temperature ◽  
Structural Reliability ◽  
Coefficient Of Thermal Expansion ◽  
Young's Modulus ◽  
Linear Thermal Expansion ◽  
Upheaval Buckling ◽  
Analysis Of Results ◽  
Mean And Variance

Material testing was undertaken on samples taken from clad pipe manufactured by JSW for the Tangguh LNG project. The test programme involved testing Young’s Modulus (E) and Coefficient of Linear Thermal Expansion (α) from room temperature to above 110° on each layer. This paper summarises testing and analysis of results which enabled mean and variance on each material property to be found. Checks were also undertaken for any correlations in properties between clad and parent layers, and between Young’s Modulus and Coefficient of Thermal Expansion. Analysis results are compared to existing industry norms and their implications for the Tangguh project UHB (Upheaval Buckling) SRA (Structural Reliability Analysis) are summarised.

Calculation of Defect Formation Energy from the Thermal Expansion Data for Lead Fluoride

1994 ◽  
Vol 369 ◽  
Author(s):  
Brenda J. Schuler ◽  
T. S. Aurora ◽  
D. O. Pederson ◽  
S. M. Day
Keyword(s):  
Thermal Expansion ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Formation Energy ◽  
Defect Formation ◽  
Coefficient Of Thermal Expansion ◽  
Linear Thermal Expansion ◽  
Lead Fluoride ◽  
Defect Formation Energy ◽  
Thermal Expansion Data

AbstractLead fluoride is a superionic conductor with the fluorite structure. Results of the measurement of linear thermal expansion of lead fluoride (reported earlier in literature) showed a large increase in the thermal expansion coefficient near 700 K where the ionic conductivity has been shown to exhibit a sharp increase. It is believed that thermally-generated defects in a crystal lattice affect the thermal expansion coefficient. This idea was applied in the present analysis to calculate the defect formation energy (Ef) by using the literature values of the coefficient of thermal expansion. It was assumed that the thermal expansion in excess of that produced due to the lattice anharmonicity (δ∝) is proportional to the concentration of defects (n). With this assumption, one may write: δ∝ = c nº exp(-Ef/kT), where c is a constant. For lead fluoride, a plot of ln(δ∝) versus (l/T) yielded Ef = 0.56 eV which is lower than the literature values. The assumptions in this analysis and the discrepancy in the result are discussed.

scholarly journals A method of manufactoring pipes from polymer composite materials for aircraft structures

2020 ◽  
Vol 26 (5) ◽  
pp. 228-27
Author(s):  
S.O. Odaisky ◽  
◽  
O.M. Potapov ◽  
S.V. Fedorenko ◽  
A.P. Shchudro ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Composite Materials ◽  
Carbon Fiber ◽  
Polymer Composite ◽  
Modulus Of Elasticity ◽  
Coefficient Of Thermal Expansion ◽  
Longitudinal Direction ◽  
Polymer Composite Materials ◽  
Thermophysical Characteristics ◽  
Reinforcement Scheme

The frame power structures are widely applied when designing aircraft, in which composite rod elements are used to reduce the mass and size characteristics. To solve the problem of manufacturing rod elements from polymer composite materials, we developed a technology for the manufacture of carbon fiber pipes using an existing machine for winding carbon fiber, which provides the necessary strength and rigidity mainly in the longitudinal direction.When calculating the rod elements, all the loads that will affect the structure as well as the coefficient of thermal expansion should be taken into account. To achieve the required physical, mechanical, and thermophysical characteristics, the optimal scheme of reinforcement is the scheme with a quasi-longitudinal direction of the fibers. We developed the method of manufacturing based on the technology allowing us to obtain a reinforcement scheme with fiber orientation in the quasi-longitudinal direction with a reinforcement angle of about 1° by a combined method of layer-by-layer winding of carbon fiber. As a result of technological testing, we obtained samples of carbon fiber rod elements, which were used to confirm the calculated characteristics. To confirm the physico-mechanical and thermophysical characteristics, we determined the assessment of limit of strength and modulus of elasticity in bending, the limit of strength and modulus of elasticity in torsion, the limit of strength and modulus of elasticity in compression, and the coefficient of thermal expansion. The obtained characteristics of the dependences of the elasticity modulus of the pipe prototype material at the fibers’ orientation angle correlate with theoretical calculations. The presented method has the patent UA 128613 U.

Investigation of micro-yield strength and coefficient of thermal expansion of Al–Cu–Mg–Li–Sc–Ag alloys with various contents of Li

2019 ◽  
Vol 34 (15) ◽  
pp. 2714-2726 ◽  
Author(s):  
Ruibin Yang ◽  
Junrui Yang ◽  
Kun Xie ◽  
Zhongxia Liu ◽  
Guotao Zhang
Keyword(s):  
Thermal Expansion ◽  
Yield Strength ◽  
Coefficient Of Thermal Expansion ◽  
Image Position

Abstract

scholarly journals Thermal analysis of metal-ceramic bonding using finite element method

2014 ◽  
Vol 3 (2) ◽  
pp. 216 ◽  
Author(s):  
S. Gopinath ◽  
R Sabarish ◽  
R. Sasidharan
Keyword(s):  
Finite Element ◽  
Thermal Expansion ◽  
Thermal Stress ◽  
Bonding Strength ◽  
Coefficient Of Thermal Expansion ◽  
Linear Thermal Expansion ◽  
Processing Temperature ◽  
Element Analysis ◽  
Metal Ceramic ◽  
The Difference

This paper reports a finite element study of effect of bonding strength between metal and ceramic. The bonding strength is evaluated with different processing temperature and holding time. The difference between the coefficients of linear thermal expansion (CTEs) of the metal and ceramic induces thermal stress at the interface. The mismatch thermal stress at the interface region plays an important role in improving bonding strength. Hence, it is essential to evaluate the interface bonding in metal-ceramics joints. The Al/SiC bonding was modeled and analyzed using finite element analysis in ANSYS (v.10). Keywords: Bonding Strength, Coefficient of Thermal Expansion, Thermal Stress, Interface, Al/Sic, FEA.

Thermal Characteristics of Cu Matrix-SiC Filler Composite Using Nano-Sized Cu Powder

2021 ◽  
Vol 21 (9) ◽  
pp. 4964-4967
Author(s):  
Bok-Hyun Oh ◽  
Choong-Hwan Jung ◽  
Heon Kong ◽  
Sang-Jin Lee
Keyword(s):  
Thermal Conductivity ◽  
Thermal Expansion ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Coefficient Of Thermal Expansion ◽  
Liquid Phase Sintering ◽  
High Thermal Conductivity ◽  
Ceramic Filter ◽  
Ceramic Filler ◽  
Significant Difference

A Cu metal-ceramic filter composite with high thermal conductivity and a suitable thermal expansion coefficient was designed to be applied to high performance heat dissipation materials. The purpose of using the ceramic filler was to decrease the high coefficient of thermal expansion of Cu matrix utilizing the high thermal conductivity of Cu. In this study, a SiC ceramic filler powder was added to the Cu sol including Zn as a liquid phase sintering agent. The final complex was produced by applying a PVB polymer to prepare a homogeneous precursor followed by sintering in a reducing atmosphere. The pressureless sintered composite showed lower thermal conductivity than pure bulk Cu due to the some residual pores. In the case of the Cu–SiC composite in which 10 wt% of SiC filler was added, it showed a thermal conductivity of 100 W/m·°C and a thermal expansion coefficient of 13.3×10−6/°C. The thermal conductivity showed some difference from the theoretical calculated value due to the pores in the composite, but the thermal expansion coefficient did not show a significant difference.

Effect of aggregate type on linear thermal expansion of self-consolidating concrete at elevated temperatures

2012 ◽  
Vol 19 (3) ◽  
pp. 259-269 ◽  
Author(s):  
Tayfun Uygunoğlu ◽  
İlker Bekir Topçu
Keyword(s):  
Thermal Expansion ◽  
Thermal Properties ◽  
Elevated Temperatures ◽  
Coefficient Of Thermal Expansion ◽  
Linear Thermal Expansion ◽  
Thermal Tests ◽  
Linear Change ◽  
Volcanic Tuff ◽  
Self Consolidating Concrete ◽  
Cement Ratio

AbstractIn this study, the effects of aggregate type on the coefficient of thermal expansion of self-consolidating concrete (SCC) produced with normal and lightweight (porous) aggregate (SCLC) were investigated. In experiments, three aggregate types, gravel, volcanic tuff, and diatomite, were used. Different combinations of water/cement ratio and superplasticizer dosage levels were prepared for the SCC and SCLC mixtures. Thermal tests were performed to accurately characterize the coefficient of thermal expansion (CTE) of SCC and SCLC aged 28 days using the dilatometer. The CTEs of SCC and SCLC were defined by measuring the linear change in length of concrete specimens subjected to a range of temperatures from 20°C to 1000°C. The results, in general, showed that SCLC has a lower CTE than that of SCC above 100°C. Moreover, CTE values of SCC and SCLC were decreased with increase in porous structure. The aggregate type has significant influence on the thermal properties of SCC.

Effect of Mechanically Activated Layered Silicate on the Properties and Structure of Polytetrafluoroethylene

2019 ◽  
Vol 945 ◽  
pp. 384-388
Author(s):  
S.A. Sleptsova ◽  
N.N. Lazareva ◽  
Yu.V. Kapitonova
Keyword(s):  
Wear Resistance ◽  
Thermal Expansion ◽  
Mechanical Activation ◽  
Polymer Matrix ◽  
Modulus Of Elasticity ◽  
Elasticity Modulus ◽  
Breaking Strength ◽  
Coefficient Of Thermal Expansion ◽  
Layered Silicate ◽  
Tribotechnical Characteristics

The results of studies of mechanical activation of mineral layered silicate - vermiculite as a method of improving compatibility with polytetrafluoroethylene (PTFE) are presented. The influence of mechanoactivation on the crystalline structure of silicate as well as on deformation-strength, tribotechnical characteristics and coefficient of thermal expansion of composites is considered. The effectiveness of the use of mechanical activation to improve the combination of vermiculite with a polymer matrix is ​​confirmed by the results of the tests. It is shown that the preliminary mechanoactivation of the layered silicate leads to an increase in the elasticity, modulus of elasticity and wear resistance of the developed composites while maintaining the breaking strength at the level of the original PTFE.

Influence of Different Curing Modes on Polymerization Behavior and Mechanical Properties of Dual-Cured Provisional Resins

2017 ◽  
Vol 42 (5) ◽  
pp. 526-536 ◽  
Author(s):  
S Shibasaki ◽  
T Takamizawa ◽  
T Suzuki ◽  
K Nojiri ◽  
A Tsujimoto ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Expansion ◽  
Filler Content ◽  
Linear Thermal Expansion ◽  
The Self ◽  
Inorganic Filler ◽  
Significant Difference ◽  
Polymerization Behavior ◽  
Light Curing ◽  
The Mean

SUMMARY This study determined the influence of curing mode on polymerization behavior and mechanical properties of dual-cured provisional resins. Three dual-cured bisacryl-based provisional resins were used: Tempsmart (TS; GC Corp), Luxatemp Automix Solar (LX; DMG Chemisch Pharmazeutishe Fabrik GmbH), and Integrity Multi·Cure (IG; Dentsply Caulk). A self-cured bisacryl-based provisional resin, Protemp Plus (PP; 3M ESPE) and a conventional poly(methyl methacrylate) (PMMA) provisional resin, Unifast III (UF; GC Corp) were used as controls. The inorganic filler content and coefficients of linear thermal expansion of the test materials were measured. Six specimens of each material were used to determine the flexural strength, elastic modulus, and resilience. The changes in ultrasound velocity during polymerization were measured. The average inorganic filler contents of the provisional resins, apart from UF, ranged from 24.4 to 39.3 wt%. The highest inorganic filler content was determined for LX, whereas TS showed the lowest value among the tested materials. The average coefficients of thermal expansion of the tested provisional resins ranged from 77.3 to 107.7 (×10−6/°C). TS and IG showed significantly lower thermal expansions than the other tested provisional resins. The mean flexural strengths of the provisional resins ranged from 70.4 to 122.6 MPa, the mean elastic moduli ranged from 1.8 to 3.7 GPa, and the mean resilience of the provisional resins ranged from 1.1 to 2.3 MJ/mm3, respectively. Dual-cured provisional resins showed significantly higher flexural strengths than the PMMA resin. However, in all cases, the light-curing mode showed significantly higher flexural strengths than the self-curing mode. In the initial polymerization phase, dual-cured resins in the light-curing mode showed a rapid increase in the speed of sound (V) during light irradiation, followed by a slower increase. Conversely, the dual-cured resins in the self-curing mode showed a slower initial increase, followed by a rapid increase. Although no significant difference in V was observed between 10 and 15 minutes in the light-curing mode of all tested dual-cured resins, a significantly higher V value was obtained at 15 minutes than at 10 minutes in the self-curing modes for LX and IG. Regardless of the curing mode, tested dual-cured provisional resins showed superior mechanical properties than the conventional PMMA provisional resin. However, dual-cured provisional resin flexural properties and polymerization behavior were affected by the curing mode. This study indicated that the light-curing mode might be recommended for all dual-cured provisional resins because of the enhancement of their mechanical properties and reduction of chair time.

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