Titanium Effect on Microstructure and Fracture toughness of Al2O3-BASED Composites

2011 ◽  
Vol 691 ◽  
pp. 32-36
Author(s):  
José G. Miranda-Hernández ◽  
Elizabeth Refugio-García ◽  
Eduardo Térres-Rojas ◽  
Enrique Rocha-Rangel
Keyword(s):  
Electron Microscopy ◽  
Fracture Toughness ◽  
Scanning Electron Microscopy ◽  
Fine Particles ◽  
Ceramic Matrix ◽  
High Energy ◽  
Titanium Content ◽  
Indentation Method ◽  
Sintered Temperature ◽  
Scanning Electron

The effect of different titanium additions (0.5, 1, 2, 3 and 10 vol. %), milling intensity (4 and 8 h) and sintered temperature (1500 and 1600 °C) on microstructure and fracture toughness of Al2O3-based composites was analyzed in this study. After high energy milling of a titanium and Al2O3mixtures, powder mixture presents fine distribution and good homogenization between ceramic and metal. After milling powders during 8 h they were obtained very fine particles with 200 nm average sizes. Microstructures of the sintered bodies were analyzed with a scanning electron microscopy, where it was observed that the microstructure presents the formation of a small and fine metallic net inside the ceramic matrix. From fracture toughness measurements realized by the fracture indentation method, it had that when titanium content in the composite increases, fracture toughness is enhanced until 83% with respect to the fracture toughness of pure Al2O3. This behavior is due to the formation of metallic bridges by titanium in the Al2O3matrix.

Effect of BN Short Fiber Content on Mechanical Properties of ZrB2-SiC UHTCs

2012 ◽  
Vol 512-515 ◽  
pp. 706-709 ◽  
Author(s):  
Chang Ling Zhou ◽  
Yan Yan Wang ◽  
Zhi Qiang Cheng ◽  
Chong Hai Wang ◽  
Rui Xiang Liu
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Fracture Toughness ◽  
Scanning Electron Microscopy ◽  
Flexural Strength ◽  
Hot Pressing ◽  
Ceramic Composites ◽  
Short Fiber ◽  
Hot Pressing Sintering ◽  
Scanning Electron

ZrB2-20%volSiC ceramic composites with different volume of BN short fiber were fabricated by the hot-pressing sintering under 2000°C. The content of BN short fiber changed from 0 to 15vol%. The density, flexural strength, fracture toughness and thermal expansions coefficient were studied. The microstructures of the samples were observed by scanning electron microscopy. The results show that the introducing of BN short fiber into the ZrB2-20%volSiC lead to a serious of change to the mechanical properties of the ceramic. When the content of the BN short fiber is 10vol%, the flexural strength and fracture toughness reach 422.1MPa and 6.15 MPa•m 1/2 respectively. And the mechanism of the increasing toughness was studied.

Mechanochemical Synthesis of Intermetallic Compounds in the Gallium–Iridium System

2019 ◽  
Vol 18 (03n04) ◽  
pp. 1940067
Author(s):  
P. Vitiaz ◽  
N. Lyakhov ◽  
T. Grigoreva ◽  
E. Pavlov
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Mechanical Activation ◽  
Intermetallic Compounds ◽  
High Energy ◽  
Planetary Mill ◽  
X Ray Diffraction ◽  
X Ray ◽  
Active Liquid ◽  
Scanning Electron

The interaction between a solid inert metal Ir and an active liquid metal Ga during mechanical activation in a high-energy planetary mill is studied by X-ray diffraction and scanning electron microscopy with high-resolution energy dispersive X-ray microanalysis. The effect of mechanical activation on the formation of GaxIry intermetallic compounds and GaxIry/Ir composites and their solubility in acids was investigated. The subsequent extraction of Ga from intermetallic compounds and composites in the mixture of concentrated acids [Formula: see text] makes it possible to produce nanoscale Ir.

SIZE REQUIREMENTS OF COMPACT SANDWICH SPECIMEN FOR TESTING OF BONE

2007 ◽  
Vol 07 (04) ◽  
pp. 419-431
Author(s):  
SATYA PRASAD PARUCHURU ◽  
ANUJ JAIN ◽  
XIAODU WANG
Keyword(s):  
Electron Microscopy ◽  
Fracture Toughness ◽  
Scanning Electron Microscopy ◽  
Bone Quality ◽  
Specimen Size ◽  
Element Analysis ◽  
Hierarchical Microstructure ◽  
Sandwich Specimen ◽  
Toughness Testing ◽  
Scanning Electron

It is well understood that bone quality deteriorates due to aging, disease, etc., and may be affected by factors at different length scales due to its hierarchical microstructure. Fracture toughness is one of the properties that assess bone quality. The compact sandwich (CS) specimen gives a better choice of bone sample size, and therefore suits a wide variety of fracture toughness testing needs and constraints. Reliable and statistically valid overall CS specimen size requirements are established in this paper; these serve as guidelines for choosing the CS specimen size. Finite element analysis (FEA) is used for simulating fracture toughness tests. Experimental fracture toughness tests are carried out to verify the FEA results. The experimental results are verified qualitatively by performing scanning electron microscopy (SEM) on the fractured specimen surfaces.

Preparation of Molybdenum High Speed Tool Steels with Addition of Niobium Carbide by Powder Metallurgy Techniques

2014 ◽  
Vol 802 ◽  
pp. 102-107 ◽  
Author(s):  
Oscar Olimpio de Araújo Filho ◽  
Rodrigo Tecchio Antonello ◽  
Cezar Henrique Gonzalez ◽  
Severino Leopoldino Urtiga Filho ◽  
Francisco Ambrozio Filho
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Powder Metallurgy ◽  
Liquid Phase ◽  
High Speed ◽  
Niobium Carbide ◽  
High Energy ◽  
Tool Steels ◽  
Vacuum Sintering ◽  
Scanning Electron

High speed steels processed by Powder Metallurgy (PM) techniques present better mechanical properties when compared with similar steels obtained by the conventional process of cast to ingot and hot working. PM techniques produce improved microstructures with smaller and better distribution of carbides. Liquid phase sintering high speed steel seems to be a cheaper processing route in the manufacturing of tool steels if compared to the well-known and expansive hot isostatic pressing high speed steels. The introduction of niobium as alloying element began with the object of replacing elements like vanadium (V) and tungsten (W). Phase liquid sintering consists in a manufacturing technique to process high speed steels by powder metallurgy. The aim of this work of research is to process and obtain AISI M2 and M3:2 with and without the addition of niobium carbide by high energy milling, cold uniaxial compaction and vacuum sintering in the presence of a liquid phase. The powders of the AISI M2 and M3:2 were processed by high energy milling adding a small quantity of niobium carbide (6% in mass), then the powders were characterized by means of X-ray diffraction (XRD) and scanning electron Microscopy (SEM) plus energy dispersion spectroscopy (EDS) in order to evaluate the milling process. The powders of the AISI M2 and M3:2 with the addition of niobium carbide (NbC) were uniaxially cold compacted and then submitted to vacuum sintering. The sintered samples had their microstructure, porosity and carbide distribution observed and evaluated by means of Scanning Electron Microscopy (SEM) and the mechanical property of hardness was investigated by means of Vickers hardness tests. At least five samples of each steel were investigated.

Characterization Techniques For Laser-Annealed Polysilicon on Insulating Layers

1980 ◽  
Vol 1 ◽  
Author(s):  
J. T. Schott ◽  
J. J. Comer
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Energy ◽  
High Energy Electron ◽  
X Ray Diffraction ◽  
X Ray ◽  
Characterization Techniques ◽  
Cw Laser ◽  
Transmission Electron ◽  
Scanning Electron

ABSTRACTVarious characterization techniques are applied to pulsed and cw laser-annealed polysilicon layers deposited on oxide layers. The results are used to compare these techniques as to the type and completeness of information provided, as well as sample preparation requirements and general ease or difficulty of measurement. The techniques employed include scanning electron microscopy (SEM), electron channeling micrographs and selected area channeling patterns (SACP), reflection (high energy) electron diffraction (RHEED), transmission electron microscopy (TEM) and selected area diffraction (SAD), x-ray diffraction, optical techniques and etching techniques.

scholarly journals Enhancement the Osseo Integration Properties of Polymer for Human Body Implants

2020 ◽  
Vol 23 (4) ◽  
pp. 331-337
Author(s):  
Dhurgham Majid Rasheed ◽  
Dunya Abdulsahib Hamdi
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Grain Boundaries ◽  
Mechanical Performance ◽  
Wear Test ◽  
High Energy ◽  
In Vitro Test ◽  
Scanning Electron

In this research, polymer polymethyl methacrylate PMMA composite with nano ceramic Zr and HAp material were used to manufacture one part of the implant system (femoral ball head of hip implant). Three set of hybrid materials were fabricated and tested for this study; the first mixtures which contains 100% (PMMA), the second mixtures which contains (90% (PMMA) + 8% (Zr) + 2% (HAp)), and the third mixtures which contains (80% (PMMA) + 18% (Zr) + 2% (HAp)) were investigated. The mechanical properties for these mixtures increased with the increasing of nano ceramic concentration (Zr and HAp) composite material in the polymer compared to pure polymer PMMA sample. However, an increase in the concentration of Zr from 8% to 18% content cause a considerable decrease of the hardness where a drop of homogeneity in Zr- matrix PMMA contact occurred, V Hardness value are (68 ,80 and 70) Kg.mm for three mixture respectively. The wear test was in agreement with results of the hardness test. The weight loss of the above samples of the wear test were (0.041, 0.035 and 0.037) respectively. According to mechanical properties, the best sample contains (90% (PMMA) + 8% (Zr) + 2% (HAp)). The Scanning electron microscopy resolute showed the particles forming semi-continuous network along grain boundaries polymer for second sample mixtures containing (90% (PMMA) + 8% (Zr) + 2% (HAp)), provides a low atomic packing and high energy. This will make the grain boundaries more reactive and strengthen mechanical performance. The Optical microscopy, Scanning electron microscopy and Xray spectroscopy analysis for In vitro test using SBF shows the growth of HAp layer with an increase in concentration of Ca and P elements formed on the surface of the second sample. This display of good results is a proof of the biocompatibility of the polymer sample.

A case study focusing on investigating the tribological performance of Cu-Sn sintered brake pad of off-high road vehicles

2020 ◽  
Vol 54 (27) ◽  
pp. 4299-4310
Author(s):  
V Vineeth Kumar ◽  
S Senthil Kumaran ◽  
S Dhanalakshmi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Energy ◽  
Friction Material ◽  
Tribological Performance ◽  
Test Machine ◽  
Brake Pad ◽  
Road Vehicles ◽  
X Ray ◽  
Scanning Electron

Copper-based sintered friction materials are most suitable for heavy-duty off-road vehicles, trains, aircraft, and military applications. This present study aims to investigate the tribological performance, dominating wear mechanism of an existing copper-tin sintered friction material that is being used in armoured fighting vehicle. The brake pad was tested as per IS 2742 using the chase test machine. Especially fade cycle was carried out till 441℃ to analyze the frictional response of the material. Physical, mechanical, and tribological properties were evaluated as per industrial standards. Morphological analysis was carried out using field emission scanning electron microscopy, and wear debris analysis was carried out using scanning electron microscopy–energy dispersive X-ray analysis and X-ray diffraction analysis. The dominating wear mechanisms were found to be delamination and abrasive wear. The investigated results showed a less wear rate of 0.05 cm3/MJ. However, results seem to be better for high-energy applications by exhibiting excellent mechanical properties.

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