scholarly journals Experimental investigations into mechanical and thermal properties of rapid manufactured copper parts

2019 ◽  
Vol 234 (1) ◽  
pp. 82-95 ◽  
Author(s):  
Gurminder Singh ◽  
Pulak M Pandey
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Ultimate Tensile Strength ◽  
Heating Rate ◽  
Sintering Temperature ◽  
Mechanical And Thermal Properties ◽  
Surface Porosity ◽  
Soaking Time ◽  
Ultrasonic Assisted

In the present paper, mechanical and thermal properties of rapidly manufactured copper parts were studied. The combination of three-dimensional printing and ultrasonic assisted pressureless sintering was used to fabricate copper parts. First, the ultimate tensile strength and thermal conductivity were compared between ultrasonic assisted and conventional pressureless sintered samples. The homogenously mixing of particles and local heat generation by ultrasonic vibrations promoted the sintering driving process and resulted in better mechanical and thermal properties. Furthermore, response surface methodology was adopted for the comprehensive study of the ultrasonic sintering parameters (sintering temperature, heating rate, and soaking time with ultrasonic vibrations) on ultimate tensile strength and thermal conductivity of the fabricated sample. Analysis of variance was performed to identify the significant factors and interactions. The image processing method was used to identify the surface porosity at different parameter levels to analyse the experimental results. High ultimate tensile strength was obtained at high sintering temperature, long soaking time, and slow heating rate with low surface porosity. After 60 min of soaking time, no significant effect was observed on the thermal conductivity of the fabricated sample. The significant interactions revealed less effect of soaking time at low sintering temperatures for ultimate tensile strength and less effect of heating rate at low sintering temperatures for thermal conductivity. Multi-objective optimization was carried out to identify parameters for maximum ultimate tensile strength and maximum thermal conductivity.

Natural Rubber-Whisker Alumina Fiber Composite Materials for Mechanical and Thermal Insulation Applications

2018 ◽  
Vol 789 ◽  
pp. 221-225
Author(s):  
Nattapol Dedruktip ◽  
Wasan Leelawanachai ◽  
Nuchnapa Tangboriboon
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Natural Rubber ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Curing Temperature ◽  
Mechanical And Thermal Properties ◽  
Alumina Fiber ◽  
Elongation At Break

Alumina fiber is a ceramic material used as a dispersed phase or filler to reinforce the mechanical and improve thermal properties of natural rubber via vulcanization process at curing temperature 150°C. The amount of alumina fiber added in natural rubber was varied from 0 to 50 phr on 100 phr of natural rubber in a sulfur curing system. Adding 10 phr alumina fiber affects to obtain the best natural rubber composite samples having good mechanical and thermal properties. Tensile strength, elongation at break, Young’s modulus and thermal conductivity of adding 10 phr whisker alumina fiber encoded NR-Al-10 are equal to 14.38±1.95 MPa, 1038.4±41.45%, 545.63±25.67 MPa and 0.2376±0.0003 W/m.K, respectively, better than those of pure natural rubber compounds without adding alumina fiber. Tensile strength, elongation at break, Young’s modulus and thermal conductivity of natural rubber without adding alumina fiber are equal to 14.06±6.03 MPa, 949.41±52.15%, 496.32±8.54 MPa and 0.2500±0.0003 W/m.K, respectively.

scholarly journals Impact of SiC on The Mechanical and Thermal Properties of Banana Fiber Reinforced Epoxy Composites

2021 ◽  
Vol 9 (9) ◽  
pp. 1066-1071
Author(s):  
Mayank Agarwal
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Thermal Properties ◽  
Thermal Diffusivity ◽  
Impact Strength ◽  
Fiber Composite ◽  
Mechanical And Thermal Properties ◽  
Fiber Reinforced ◽  
Banana Fiber ◽  
Banana Fibers

Abstract: This work investigates the mechanical properties (Tensile Strength & Impact Strength) and thermal properties (Thermal conductivity & diffusivity) of a natural fiber composite that includes banana fiber as reinforcement in epoxy (LY 556) matrix as the base material with the addition of silicon carbide particles by 5% and 10% by weight. This Banana Fiber Reinforced Epoxy Composite (BFREC) prepared by hand lay-up technique. After curing for a sufficient period, samples taken out and tested. The results suggest that on increasing SiC wt% in the matrix, there is enhancement of its tensile strength, impact strength, and thermal conductivity. Bulk density also increases while thermal diffusivity decreases. Due to low density as compared to metals, improved tensile and impact strength and low elongation at break of banana fibers, BFREC composite with SiC have very good potential use in the various sectors. Keywords: Banana fiber, SiC, hand layup technique, mechanical characterization, thermal conductivity, thermal diffusivity

Reinforcing of low-density polyethylene by cellulose extracted from agricultural wastes

2018 ◽  
Vol 53 (2) ◽  
pp. 219-225 ◽  
Author(s):  
Shadi Sawalha ◽  
Raed Ma'ali ◽  
Omar Surkhi ◽  
Mohammad Sawalha ◽  
Bayan Dardouk ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Thermal Properties ◽  
Ultimate Tensile Strength ◽  
Solid Waste ◽  
Agricultural Wastes ◽  
Degree Of Crystallinity ◽  
Low Density Polyethylene ◽  
Mechanical And Thermal Properties ◽  
Low Density ◽  
Cellulosic Materials

Cellulosic materials were extracted from different agricultural wastes such as corn stalks, olive solid waste, and wood, by using a suitable extraction method. The extracted cellulosic materials were characterized using Fourier transform infrared spectroscopy. The produced cellulosic materials were used as reinforcements for low-density polyethylene to improve its tensile and thermal properties. A two-roll mill was used to mix the cellulosic materials (2.5–10 wt.%) with low-density polyethylene , and then the composite sheets were prepared by using a thermal press molding. The effects of filler type and its content on the mechanical and thermal properties were investigated by using the universal testing machine and differential scanning calorimeter, respectively. In general, with the increase of cellulosic materials content, there is an increase in the modulus of elasticity of the produced composites and a decrease of ductility. The ultimate tensile strength of the produced composites based on low-density polyethylene and cellulosic materials extracted from corn stalks and olive solid waste was found to be less than the tensile strength of low-density polyethylene, whereas the ultimate tensile strength of the composites based on low-density polyethylene and cellulose powder extracted from wood increased with increasing the cellulosic content. The addition of cellulosic materials was found to affect both the melting temperature of low-density polyethylene and its degree of crystallinity, depending on the cellulosic material source.

scholarly journals Mechanical and Thermal Properties of UHPC Exposed to High-Temperature Thermal Cycling

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
In-Hwan Yang ◽  
Jihun Park
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Thermal Properties ◽  
High Temperature ◽  
Thermal Cycling ◽  
Steel Fiber ◽  
Unit Weight ◽  
Maximum Temperature ◽  
Mechanical And Thermal Properties

The effects of high-temperature thermal cycling (temperatures up to 500°C) and steel fiber contents on the mechanical and thermal properties of ultrahigh-performance concrete (UHPC) containing polypropylene (PP) fibers were investigated in this study. The different maximum temperatures for thermal cycling included 300, 400, and 500°C. The mechanical properties, including the compressive strength and tensile strength, and thermal properties, including the unit weight and thermal conductivity, of the UHPC specimens were measured. The experimental results indicated that the compressive strength, tensile strength, unit weight, and thermal conductivity decreased as the temperature increased to 500°C. Test results showed that for each maximum temperature, the reduction of the thermal conductivities from one to six thermal cycles was not significant. The thermal conductivity of the UHPC decreased as the unit weight of the UHPC decreased, and the thermal conductivity also decreased as the compressive strength of the UHPC decreased. Scanning electron microscopy (SEM) analysis showed that the microstructures of the UHPC specimens exposed to high temperatures contained voids due to the PP fiber melting. The porosity of the UHPC specimens increased as the maximum temperature of the thermal cycles increased, which decreased the unit weights and thermal conductivities of the UHPC specimens. Moreover, the porosity at a temperature of 500°C increased by 60.0, 74.5, and 123.4% for steel fiber contents of 1.0, 1.5, and 2.0%, respectively. It might be due to incompatible thermal expansion between the concrete matrix and steel fiber.

Mechanical and thermal properties of glass fibre-reinforced ceramsite-foamed concrete

2017 ◽  
Vol 27 (7) ◽  
pp. 890-897 ◽  
Author(s):  
Guoxin Chen ◽  
Kang Wang
Keyword(s):  
Thermal Conductivity ◽  
Hydrogen Peroxide ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Glass Fibre ◽  
Splitting Tensile Strength ◽  
Mechanical And Thermal Properties ◽  
Foamed Concrete ◽  
Glass Fibre Reinforced

This study investigated the mechanical and thermal properties of glass fibre-reinforced ceramsite-foamed concrete with a volume of entrained air generated by hydrogen peroxide. The effects of hydrogen peroxide content, glass fibre content, glazed hollow bead content and ceramsite content on the compressive strength, splitting tensile strength and thermal conductivity were investigated. The results indicated that with the addition of hydrogen peroxide and an increase in glazed hollow bead and ceramsite content, there was a significant increase in the brittleness of foamed concrete. Glass fibre can obviously improve the splitting tensile strength and reduce the thermal conductivity of foamed concrete. In addition, an empirical compressive strength formula of glass fibre-reinforced ceramsite-foamed concrete was recommended.

Effects of Trace Elements on Thermal and Mechanical Properties of Al–Zn–Cu Based Alloys Using Extrusion

2020 ◽  
Vol 20 (7) ◽  
pp. 4216-4220
Author(s):  
Yong-Ho Kim ◽  
Hyo-Sang Yoo ◽  
Hyeon-Taek Son
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Tensile Strength ◽  
Trace Elements ◽  
Thermal Properties ◽  
Ultimate Tensile Strength ◽  
Extrusion Direction ◽  
Hot Extrusion ◽  
Thermal And Mechanical Properties ◽  
Cu Alloy

Thermal properties and microstructure of Al-4 wt.% Zn-2 wt.% Cu–x (x = 2 wt%. Mg, 2 wt%. Sn, 0.7 wt.% Mg-0.7 wt.% Sn-0.7 wt.% Ca) alloys on cast and extrusion have been investigated with extrusion temperature of 400 °C. Al-4 wt.% Zn-2 wt.% Cu alloy was composed of Al and Al2Cu phases. By adding Mg contents, Al2Mg3Zn3 phase was increased and Al2Cu phase was decreased respectively. During hot extrusion, elongated in the extrusion direction because of severe deformation. The thermal conductivity with temperature and composition of as-extruded Al-4 wt.% Zn-2 wt.% Cu–x alloys decreases with adding 2 wt.% Mg, 2 wt.% Sn contents from 190.925 and 196.451 W/mK but thermal properties of addition of 0.7 wt.% Mg-0.7 wt.% Sn-0.7 wt.% Ca element slightly reduced from 222.32 to 180.775 W/mK. The ultimate tensile strength (UTS) for Al-4 wt.% Zn- 2 wt.% Cu alloy was 121.67 MPa. By adding 2 wt.% Mg contents, tensile strength was dramatically increased with 350.5 MPa.

The Study of Thermal Properties and Micro Structures of YSZ

2007 ◽  
Author(s):  
S. M. Guo ◽  
M. B. Silva ◽  
Patrick F. Mensah ◽  
Nalini Uppu
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Gas Turbine ◽  
Bond Coat ◽  
Sintering Temperature ◽  
Heating Process ◽  
Thermal Barrier ◽  
Inlet Temperature ◽  
Low Thermal Conductivity ◽  
Gas Tight

Thermal barrier coatings (TBCs) are used in gas turbine engines to achieve a better efficiency by allowing increased turbine inlet temperature and decreasing the amount of cooling air used. Plasma spraying is one of the most reliable methods to produce TBCs, which are generally comprised of a top coating of ceramic and a bond-coat of metal. Usually, the top coating is Yttria-Stabilized-Zirconia (YSZ), providing the thermal barrier effect. The bond-coat is typically a layer of M-Cr-Al-Y (where “M” stands for “metal”), employed to improve the attachment between the ceramic top-coat and the substrate. Due to the extreme temperature gradient presented in the plasma jet and the wide particle size distribution, during the coating process, injected ceramic powders may experience a significantly different heating process. Different heating history, coupled with the substrate preheating temperature, may affect the thermal properties of the YSZ layers. In this paper, four sets of mol 8% YSZ disks are fabricated under controlled temperatures of 1100°C, 1200°C, 1400°C and 1600°C. Subsequently the thermal properties and the microstructures of these YSZ disks are studied. The results indicate a strong microstructure change at a temperature slightly below 1400°C. For a high sintering temperature, a dense YSZ layer can be formed, which is good for gas tight operation; At low sintering temperature, say 1200°C, a porous YSZ layer is formed, which has the advantage of low thermal conductivity. For gas turbine TBC applications, a robust low thermal conductivity YSZ layer is desirable, while for Solid Oxide Fuel Cells, a gas-tight YSZ film must be formed. This study offers a general guideline on how to prepare YSZ layers, mainly by controlling the heating process, to form microstructures with desired properties.

Mechanical and Thermal Properties of Magnesia Binder Based on Natural and Technogenic Raw Materials

2021 ◽  
Vol 320 ◽  
pp. 181-185
Author(s):  
Elvija Namsone ◽  
Genadijs Sahmenko ◽  
Irina Shvetsova ◽  
Aleksandrs Korjakins
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Raw Materials ◽  
High Strength ◽  
Strength Properties ◽  
Waste Materials ◽  
Mechanical And Thermal Properties ◽  
Experimental Part ◽  
Technogenic Raw Materials ◽  
Caustic Magnesia

Because of low calcination temperature, magnesia binders are attributed as low-CO2 emission materials that can benefit the environment by reducing the energy consumption of building sector. Portland cement in different areas of construction can be replaced by magnesia binder which do not require autoclave treatment for hardening, it has low thermal conductivity and high strength properties. Magnesium-based materials are characterized by decorativeness and ecological compatibility.The experimental part of this research is based on the preparation of magnesia binders by adding raw materials and calcinated products and caustic magnesia. The aim of this study was to obtain low-CO2 emission and eco-friendly material using local dolomite waste materials, comparing physical, mechanical, thermal properties of magnesium binders.

scholarly journals Bio-based rigid polyurethane foam prepared from apricot stone shell-based polyol for thermal insulation application – Part 2: Morphological, mechanical, and thermal properties

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6080-6094
Author(s):  
Muhammed Said Fidan ◽  
Murat Ertaş
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Polyurethane Foam ◽  
Flame Retardants ◽  
Compressive Modulus ◽  
Cell Diameter ◽  
Mechanical And Thermal Properties ◽  
Rigid Polyurethane Foam

The procedure for the liquefaction of apricot stone shells was reported in Part 1. Part 2 of this work determines the morphological, mechanical, and thermal properties of the bio-based rigid polyurethane foam composites (RPUFc). In this study, the thermal conductivity, compressive strength, compressive modulus, thermogravimetric analysis, flammability tests (horizontal burning and limited oxygen index (LOI)) in the flame retardants), and scanning electron microscope (SEM) (cell diameter in the SEM) tests of the RPUFc were performed and compared with control samples. The results showed the thermal conductivity (0.0342 to 0.0362 mW/mK), compressive strength (10.5 to 14.9 kPa), compressive modulus (179.9 to 180.3 kPa), decomposition and residue in the thermogravimetric analysis (230 to 491 °C, 15.31 to 21.61%), UL-94 and LOI in the flame retardants (539.5 to 591.1 mm/min, 17.8 to 18.5%), and cell diameter in the SEM (50.6 to 347.5 μm) of RPUFc attained from liquefied biomass. The results were similar to those of foams obtained from industrial RPUFs, and demonstrated that bio-based RPUFc obtained from liquefied apricot stone shells could be used as a reinforcement filler in the preparation of RPUFs, specifically in construction and insulation materials. Moreover, liquefied apricot stone shell products have potential to be fabricated into rigid polyurethane foam composites.

Influence of Palm Oil Fibers Length Variation on Mechanical Properties of Reinforced Crude Bricks

2022 ◽  
Author(s):  
Mazhar Hussain ◽  
Daniel Levacher ◽  
Nathalie Leblanc ◽  
Hafida Zmamou ◽  
Irini Djeran Maigre ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Composite Materials ◽  
Physical Properties ◽  
Palm Oil ◽  
Mechanical Characteristics ◽  
Natural Fibers ◽  
Indirect Tensile

Crude bricks are composite materials manufactured with sediments and natural fibers. Natural fibers are waste materials and used in construction materials for reinforcement. Their reuse in manufacturing reinforced crude bricks is eco-friendly and improves mechanical and thermal characteristics of crude bricks. Factors such as type of fibers, percentage of fibers, length of fibers and distribution of fibers inside the bricks have significant effect on mechanical, physical and thermal properties of biobased composite materials. It can be observed by tests such as indirect tensile strength, compressive strength for mechanical characteristics, density, shrinkage, color for physical properties, thermal conductivity and resistivity for thermal properties, and inundation test for durability of crude bricks. In this study, mechanical and physical characteristics of crude bricks reinforced with palm oil fibers are investigated and effect of change in percentage and length of fibers is observed. Crude bricks of size 4*4*16 cm3 are manufactured with dredged sediments from Usumacinta River, Mexico and reinforced with palm oil fibers at laboratory scale. For this purpose, sediments and palm oil fibers characteristics were studied. Length of fibers used is 2cm and 3cm. Bricks manufacturing steps such as sediments fibers mixing, moulding, compaction and drying are elaborated. Dynamic compaction is opted for compaction of crude bricks due to energy control. Indirect tensile strength and compressive strength tests are conducted to identify the mechanical characteristics of crude bricks. Physical properties of bricks are studied through density and shrinkage. Durability of crude bricks is observed with inundation test. Thermal properties are studied with thermal conductivity and resistivity test. Distribution and orientation of fibers and fibers counting are done to observe the homogeneity of fibers inside the crude bricks. Finally, comparison between the mechanical characteristics of crude bricks manufactured with 2cm and 3cm length with control specimen was made.

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