scholarly journals Tribological, Thermal and Corrosive behaviour of aluminium alloy 2219 reinforced by Si3N4 nanosized powder

2021 ◽  
Author(s):  
Manjunatha C J ◽  
B. Venkata Narayana ◽  
D Bino Prince Raja ◽  
Rimal Isaac R S
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Aluminium Alloy ◽  
Corrosion Behaviour ◽  
Thermo Gravimetric Analysis ◽  
Stir Casting ◽  
High Energy ◽  
Gravimetric Analysis ◽  
Test Pieces ◽  
Scanning Electron

Abstract The MMC technique is the most effective contrast method when compared with other techniques. By using the method of high energy stir casting, Aluminium alloy Al2219 is reinforced with various percentages of Si3N4 (0, 3, 6, and 9%) particles. X-ray diffraction along with Scanning electron microscope was performed to characterize the composite. The mechanical and thermal behaviours such as differential thermal analysis thermo gravimetric analysis/, tensile , wear and hardness behaviours were investigated. By using electro chemical potentiodynamic polarization test, the consequence of heat treatment on the corrosion behaviour of the composites when compared to its matrix in 3.5 % NaCl when at 600 rpm was also investigated. In this experimental study, the wear of the aluminium composites was significantly decreased on addition of Si3N4 particles. The study also revealed that, since the inclusion of Si3N4 in the samples and compared to the base aluminium alloy, the mechanical properties of the composites, such as wear resistance , hardness and tensile strength increased by percentage. The surface morphology and Scanning electron microscope analysis of worn surfaces in the test pieces unfold that with the increase in reinforcement content, wear rate decreases.

MICRO-FOUR-POINT PROBES IN A UHV SCANNING ELECTRON MICROSCOPE FOR IN-SITU SURFACE-CONDUCTIVITY MEASUREMENTS

2000 ◽  
Vol 07 (05n06) ◽  
pp. 533-537 ◽  
Author(s):  
ICHIRO SHIRAKI ◽  
TADAAKI NAGAO ◽  
SHUJI HASEGAWA ◽  
CHRISTIAN L. PETERSEN ◽  
PETER BØGGILD ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Surface Defects ◽  
High Energy ◽  
Surface Conductivity ◽  
Conductivity Measurements ◽  
Surface Domains ◽  
Unambiguous Detection ◽  
Scanning Electron

For in-situ measurements of surface conductivity in ultrahigh vacuum (UHV), we have installed micro-four-point probes (probe spacings down to 4 μm) in a UHV scanning electron microscope (SEM) combined with scanning reflection–high-energy electron diffraction (RHEED). With the aid of piezoactuators for precise positioning of the probes, local conductivity of selected surface domains of well-defined superstructures could be measured during SEM and RHEED observations. It was found that the surface sensitivity of the conductivity measurements was enhanced by reducing the probe spacing, enabling the unambiguous detection of surface-state conductivity and the influence of surface defects on the electrical conduction.

Surface ornamentation of the echinoid test and its ecologic significance

Paleobiology ◽  
1976 ◽  
Vol 2 (2) ◽  
pp. 122-130 ◽  
Author(s):  
Susan C. Oldfield
Keyword(s):  
Growth Rate ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Outer Surface ◽  
High Growth ◽  
High Energy ◽  
Low Energy ◽  
Plate Surface ◽  
Surface Ornamentation ◽  
Scanning Electron

A scanning electron microscope survey of the regular echinoid test reveals that the outer surface of its component coronal plates may be sculptured with a fine-relief ornament that is species-characteristic for those species presently surveyed. Structural resemblances in surface ornamentation are more marked in species living in similar habitats than in those species that are apparently phyletically related. Plate ornament is related to skeletal magnesium levels. It is tentatively suggested that low growth rate echinoids that inhabit “low-energy” environments (and exhibit low total skeletal magnesium levels) and “high-energy” habitat-exploiting species with high growth rates (and relatively high skeletal magnesium levels) may have differential patterns of plate growth that can be distinguished by the degree of ornamentation of the plate surface.

scholarly journals Preparation and characterization of a novel bacterial cellulose/chitosan bio-hydrogel

2017 ◽  
Vol 7 ◽  
pp. 184798041770717 ◽  
Author(s):  
Yuanyuan Jia ◽  
Xiaohong Wang ◽  
Mingming Huo ◽  
Xiaoli Zhai ◽  
Fei Li ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Atomic Force Microscope ◽  
Bacterial Cellulose ◽  
Crystallinity Index ◽  
Growth Media ◽  
Published Data ◽  
Gravimetric Analysis ◽  
Atomic Force ◽  
Scanning Electron

Composites of chitosan chloride and bacterial cellulose were successfully prepared by in situ method. Composites of bacterial cellulose/chitosan and pristine bacterial cellulose were investigated by means of scanning electron microscope, atomic force microscope, Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, and bacteriostatic test. The crystallization of bacterial cellulose was interfered and weakened by the chitosan chloride included in the growth media, resulting in lower crystallinity index and thermal stability. And interaction between two polymers is verified by the thermal gravimetric analysis. The ultrafine nanofibril network structure of bacterial cellulose was retained by the composites, while the diameters were larger and the aperture inside were smaller than those of pristine bacterial cellulose, as shown through scanning electron microscope and atomic force microscope figures. The antimicrobial effects were enhanced by the increasing concentration of chitosan in composites. All the characteristics of the composites provide evidence for the miscibility of chitosan and cellulose. Their biocompatibility is proved through our published data. It is strongly indicated that bacterial cellulose–chitosan nanocomposites have great potential in tissue engineering or pharmaceutical applications in the near future.

Mechanical Alloying for Fabrication of Fe50Ni30B20 Amorphous Alloys Powder

2011 ◽  
Vol 298 ◽  
pp. 215-219
Author(s):  
Ge Wang ◽  
Zhi Gang Chao ◽  
Yu Ying Zhu ◽  
Dong Dong Hu ◽  
Xing Hua Wang ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Thermodynamic Properties ◽  
Scanning Electron Microscope ◽  
Mechanical Alloying ◽  
Amorphous Alloys ◽  
Ball Mill ◽  
Milled Powder ◽  
High Energy ◽  
X Ray ◽  
Scanning Electron

Fe50Ni30B20 amorphous Alloys powder was prepared by mechanical alloying (MA) with a high-energy planetary ball mill. The composition and non-crystallization changing process of the as-milled powder were studied by X-ray diffractometry (XRD). The microstructure and shape of the amorphous alloys powder was observed by scanning electron microscope (SEM). Thermodynamic properties and crystallization kinetics behavior of the as-milled amorphous alloys powder were measured by differential scanning calorimeter (DSC).

scholarly journals ANALISIS PENGARUH KANDUNGAN SIC, TEMPERATUR CAIRAN, KECEPATAN PUTAR DAN DURASI WAKTU PENGADUKAN PADA KEKUATAN TARIK KOMPOSIT AL-SIC

ROTASI ◽  
2014 ◽  
Vol 16 (1) ◽  
pp. 7 ◽  
Author(s):  
Sadi Sadi ◽  
M. Waziz Wildan ◽  
Suyitno Suyitno
Keyword(s):  
Silicon Carbide ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Stir Casting ◽  
Scanning Electron

Tujuan penelitian ini adalah untuk menganalisis pengaruh kandungan SiC, temperatur cairan, kecepatan putar dan durasi waktu pengadukan pada kekuatan tarik komposit Al-SiC menggunakan metode Taguchi. Material komposit yang digunakan adalah aluminium paduan Al-Si sebagai matrik dan partikel SiC (silicon carbide) ukuran -400 mesh sebagai penguat. Spesimen komposit Al-SiC dibuat menggunakan proses stir casting. Kekuatan tarik spesimen komposit Al-SiC diuji menggunakan mesin uji tarik servopulser. Kandungan SiC, temperatur  cairan, kecepatan putar dan durasi waktu pengadukan, masing-masing menggunakan 4 variasi. Hasil eksperimen menunjukkan bahwa menaikkan kecepatan putar pengadukan sampai 300 rpm dan durasi waktu pengadukan sampai 30 menit mampu menaikkan kekuatan tarik komposit Al-SiC, tetapi menaikkan kandungan SiC di atas 5 % berat dan temperatur cairan di atas 680oC dapat menurunkan kekuatan tariknya. Kandungan SiC pengaruhnya paling besar pada kekuatan tarik komposit Al-SiC dengan kontribusi 68,86 %. Sruktur mikro coran komposit Al-SiC diamati menggunakan scanning electron microscope (SEM).

An experimental study on the deformation behaviour and fracture mode of recycled aluminium alloy AA6061-reinforced alumina oxide undergoing high-velocity impact

2020 ◽  
Vol 234 (23) ◽  
pp. 4659-4670
Author(s):  
MK Mohd Nor ◽  
CS Ho ◽  
FNA Janudin
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Aluminium Alloy ◽  
Impact Velocity ◽  
Damage Evolution ◽  
Deformation Behaviour ◽  
Alumina Oxide ◽  
Impact Area ◽  
The Impact ◽  
Scanning Electron

The anisotropic behaviour and the damage evolution of recycled aluminium alloy-reinforced alumina oxide are investigated in this paper using Taylor impact test. The test is performed at various impact velocity ranging from 190 to 360 m/s by firing a cylindrical projectile towards anvil target. The deformation behaviour and the fracture modes are analysed using the digitized footprint of the deformed specimens. The damage initiation and the progression are observed around the impact surface and the surface 0.5 cm from the impact area using the scanning electron microscope. The deformed specimens showed several ductile fracture modes of mushrooming, tensile splitting and petalling. The critical impact velocity is defined below 280 m/s. The specimens showed a strong strain-rate dependency due to the damage evolution that is driven by severe localized plastic-strain deformation. The scanning electron microscope analysis showed the damage mechanism progress via voids initiation, growth and coalescence in the material. The micrograph within the footprint surface shows the presence of alumina oxide particles within the specimen. The microstructure analysis shows a significant refinement of the specimen particle at the surface located 0.5 cm above the impact area. ImageJ software is adopted in this work to measure the average size of voids within this surface. Non-symmetrical (ellipse-shaped) footprint around the footprints showed plastic anisotropic behaviour. The results in this paper provide a better understanding of the deformation behaviour of recycled materials subjected to dynamic loading. This information on mechanical response is crucial before any potential application can be established to substitute the primary sources.

scholarly journals Effect of Quartz-Silicon Dioxide Particulate on Tensile Properties of Aluminium Alloy Cast Composites

2011 ◽  
Vol 471-472 ◽  
pp. 727-732 ◽  
Author(s):  
Mohd Sayuti ◽  
Shamsuddin Sulaiman ◽  
B.T. Hang Tuah Baharudin ◽  
Mohd Khairol A. Arifin ◽  
T.R. Vijayaram ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Silicon Dioxide ◽  
Aluminium Alloy ◽  
Tensile Properties ◽  
Tensile Tests ◽  
Moulding Process ◽  
Particulate Reinforced ◽  
Scanning Electron

This paper describes an experimental investigation of the tensile properties of quartz-silicon dioxide particulate reinforced LM6 aluminium alloy composite. In this experimental, quartz-silicon dioxide particulate reinforced LM6 composite were fabricated by carbon dioxide sand moulding process with variation of the particulate content on percentage of weight. Tensile tests were conducted to determine tensile strength and modulus of elasticity followed by fracture surface analysis using scanning electron microscope to characterize the morphological aspects of the test samples after tensile testing. The results show that the tensile strength of the composites decreased with increasing of quartz particulate content. In addition, this research article is well featured by the particulate-matrix bonding and interface studies which have been conducted to understand the processed composite materials mechanical behaviour. It was well supported by the fractographs taken using the scanning electron microscope (SEM). The composition of SiO2 particulate in composite was increased as shown in EDX Spectrum and Fractograph.

Sign in / Sign up

Export Citation Format

Share Document