scholarly journals An Investigation of Wear Behaviors of AA7075 Al Hybrid Composites

2018 ◽  
Vol 37 (7) ◽  
pp. 619-624 ◽  
Author(s):  
Musa Yıldırım ◽  
Dursun Özyürek
Keyword(s):  
Hybrid Composites ◽  
Wear Behavior ◽  
Wear Test ◽  
Ex Situ ◽  
Powder Metallurgy Method ◽  
Test Results ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Weight Losses

AbstractThis study investigates the wear behavior of Al hybrid composites produced by adding 4 % Ti and different amounts of B4C (ex situ) to the AA7075 alloy produced by powder metallurgy method in order to obtain TiAl3 (in situ) reinforcement phase. Different amounts of B4C (3 %, 6 % and 9 %) were added to the 4 % Ti added AA7075 alloy. Preformed parts were sintered in controlled atmosphere (argon) heat treatment furnace at 580 °C for 4 hours and then cooled. After the sintering process, the samples were characterized with scanning electron microscopy, X-ray diffraction and density and hardness measurements. Wear tests of the samples were conducted at 1ms-1 sliding speed, under 30N load for 6 different sliding distances (500–3000 m). As a result of the study, the density of the AA7075 alloys, added 4 % Ti and different amounts of B4C, was observed to decrease by the increasing amount of reinforcement elements. Also, the highest hardness value was measured for the 9 % B4C added AA7075 alloy. Wear test results showed that the weight loss of the aluminum hybrid composites increased with the increasing sliding distance. On the other hand, it was observed that weight losses of composites decreased with increasing amount of B4C.

Effect of nano Al2O3 coated Ag reinforced Cu matrix nanocomposites on mechanical and tribological behavior synthesis by P/M technique

2020 ◽  
Vol 54 (30) ◽  
pp. 4921-4928
Author(s):  
A Mohamed ◽  
MM Mohammed ◽  
AF Ibrahim ◽  
Omyma A El-Kady
Keyword(s):  
Wear Behavior ◽  
Composite Coatings ◽  
Microstructural Analysis ◽  
Wear Test ◽  
Test Results ◽  
X Ray Diffraction ◽  
X Ray ◽  
Average Hardness ◽  
Ag Particles ◽  
Matrix Nanocomposites

In this study, copper powder was reinforced with different weight percentages of Al2O3 particles (0, 5, 10, and 15 wt.% Al2O3 coated Ag) to produce Cu-Al2O3 composites by mechanical alloying and uniaxial cold pressing/sintering route. Electro-less deposition was used to coat Al2O3 particles with Ag. The microstructure of the consolidated samples was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) elemental mapping. The porosity, microhardness, and wear behavior of the consolidated samples were also investigated as a function of Al2O3 content. The EDX mapping images reveal that the Al2O3 reinforcement particles were homogeneously distributed into the Cu matrix. Microstructural analysis shows that the addition of Al2O3 coated Ag particles improves density of the composites coating. SEM micrographs result shows that slight porosities exist in the composites produced. Furthermore, the average hardness of the composite coatings varies from 72.3 to 187.6 HV as Al2O3 content increases from 0 to 15 wt.%. The wear test results showed that the composite with higher Al2O3 content 15 wt.% showed the best wear resistance.

Effect of Varying Wt% of TiC on Mechanical and Wear Properties of RZ5-TiC In-Situ Composite

2018 ◽  
Vol 8 (2) ◽  
pp. 45-56 ◽  
Author(s):  
Deepak Mehra ◽  
M.M. Mahapatra ◽  
S. P. Harsha
Keyword(s):  
Wear Resistance ◽  
Wear Behavior ◽  
Wear Test ◽  
X Ray Diffraction ◽  
Wear Properties ◽  
X Ray ◽  
Tic Particle ◽  
Mechanical And Microstructural Properties ◽  
Sliding Distance

The purpose of this article is to enhance the mechanical properties and wear resistance of the RZ5 alloy used in the aerospace application by adding TiC particles. The present study discusses processing of in-situ RZ5-TiC composite fabricated by self-propagating high temperature (S.H.S.) method and its wear behavior. The effects of TiC particle on mechanical and microstructural properties of the composite are studied. The wear test is performed by varying the sliding distance and applied load. The composite is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The results exhibited the properties like strength and hardness of RZ5-10wt%TiC composite has been increased considerably, while grain size is decreased as compared to the RZ5 alloy. The fractography indicated mixed mode (quasi-cleavage and ductile feature) failure of the composites. The wear results showed improvement in wear resistance of the composite. The FESEM showed dominate wear mechanisms are abrasion, ploughing grooves.

Electrochemical Behavior of Li4Ti5O12 under In Situ Process of Sintering and Surface Coating with Cassava Powder

2013 ◽  
Vol 789 ◽  
pp. 21-27 ◽  
Author(s):  
Bambang Prihandoko ◽  
Achmad Subhan ◽  
Slamet Priyono
Keyword(s):  
Raw Materials ◽  
Active Material ◽  
Stoichiometric Composition ◽  
Life Time ◽  
Cassava Starch ◽  
Powder Metallurgy Method ◽  
Test Results ◽  
Sintering Process ◽  
Black Color

Anode active material Li4Ti5O12/C has an advantage to increase the life time and the ability to charge and discharge lithium batteries. An experiment was carried out to make Li4Ti5O12/C more cheaper and simple process. Preparation of Li4Ti5O12/C was carried out with stoichiometric composition of raw materials TiO2 (Merck) and LiOH.H2O (Germany) under powder metallurgy method. After mixing and calcinations cassava starch as a source of carbon black coating could be mixed under comparison 1:1 with calcinations powders. Pyrolisis process was done in - situ by the sintering process at temperature variation, i.e. 800, 850 and 900°C for 1 hour. XRD test results indicated the presence of anatase TiO2 entire sample. The best results of powder Li4Ti5O12/C with in situ process under 850°C for 1 hour had conductivity in the order of 10-4S/cm and capacity round 5mAh/g. Carbon coating of cassava starch that is well identify in the black color of sample powder and EDX analysis, gave influence on electrochemical graphics of oxidation and reduction by cyclic voltammeter. The working voltage of Li4Ti5O12/C is in general 1.55V.

Production of V(C,N) Reinforced Iron Matrix Composites

2012 ◽  
Vol 182-183 ◽  
pp. 158-161 ◽  
Author(s):  
Cheng Hua Zhu
Keyword(s):  
Matrix Composite ◽  
Sliding Wear ◽  
Wear Behavior ◽  
Wear Test ◽  
Dry Sliding Wear ◽  
Matrix Composites ◽  
X Ray Diffraction ◽  
Iron Matrix ◽  
Reinforced Composite

The present work reported the preparation of V(C,N)-reinforced iron matrix composite via in situ synthesis. The phases and morphologies of the sintered composite were investigated using X-ray diffraction (XRD) and scanning electron microscopy(SEM). Dry sliding wear test had been carried out to study the wear behavior of V(C,N)-reinforced iron matrix composite. The results show that a uniform distribution of the V(C,N) reinforcing phase throughout the iron matrix is successfully obtained. Compared with hardened 45 steel, the wear resistance of the V(C,N)-reinforced composite is better

In Situ X-Ray Diffraction Investigations during Diffusion Anneals of Ni-Cu Thin Film Diffusion Couples

2010 ◽  
Vol 89-91 ◽  
pp. 503-508 ◽  
Author(s):  
J. Sheng ◽  
U. Welzel ◽  
Eric J. Mittemeijer
Keyword(s):  
Thermal Stresses ◽  
Stress Generation ◽  
Ex Situ ◽  
Diffusion Annealing ◽  
X Ray Diffraction ◽  
Individual Layer ◽  
X Ray ◽  
Bilayer System ◽  
Stress Changes

The stress evolution during diffusion annealing of Ni-Cu bilayers (individual layer thicknesses of 50 nm) was investigated employing ex-situ and in-situ X-ray diffraction measurements. Annealing at relatively low homologous temperatures (about 0.3 - 0.4 Tm) for durations up to about 100 hours results in considerable diffusional intermixing, as demonstrated by Auger-electron spectroscopy investigations (in combination with sputter-depth profiling). In addition to thermal stresses due to differences of the coefficients of thermal expansion of layers and substrate, tensile stress con-tributions in the sublayers arise during the diffusion anneals. The obtained stress data have been discussed in terms of possible mechanisms of stress generation. The influence of diffusion on stress development in the sublayers of the diffusion couple during heating and isothermal annealing was investigated by comparing stress changes in the bilayer system with corresponding results obtained under identical conditions for single layers of the components in the bilayer system. The specific residual stresses that emerge due to diffusion between the (sub)layers in the bilayer could thereby be identified.

Size dependent behavior of Fe3O4crystals during electrochemical (de)lithiation: an in situ X-ray diffraction, ex situ X-ray absorption spectroscopy, transmission electron microscopy and theoretical investigation

2017 ◽  
Vol 19 (31) ◽  
pp. 20867-20880 ◽  
Author(s):  
David C. Bock ◽  
Christopher J. Pelliccione ◽  
Wei Zhang ◽  
Janis Timoshenko ◽  
K. W. Knehr ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Structural Changes ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
X Ray ◽  
Size Dependent ◽  
Transmission Electron ◽  
Dependent Behavior ◽  
X Ray Absorption

Crystal and atomic structural changes of Fe3O4upon electrochemical (de)lithiation were determined.

scholarly journals A study on preparation and characterization of carbon doped TiO2 nanotubes

2014 ◽  
Vol 6 (1) ◽  
Author(s):  
Srimala Sreekantan ◽  
Roshasnorlyza Hazan ◽  
Zainovia Lockman ◽  
Ishak Mat
Keyword(s):  
Methyl Orange ◽  
Tio2 Nanotubes ◽  
Pure Tio2 ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
Methyl Orange Degradation ◽  
Doped Tio2 ◽  
X Ray ◽  
Carbon Doped

The present study is directed to clarify the influence of carbon doping on the degradation of methyl orange. TiO2 nanotubes were prepared by anodizing titanium foils in a two electrode configuration bath with titanium foil as the anode and platinum as the counter electrode. The electrochemical bathconsists of 1 M Na2SO4 with 0.7 g ammonium fluoride, NH4F. The nanotubes obtained were further doped with carbon via in-situ and ex-situ method. Incorporation of carbon on TiO2 via in-situ method is accomplished during the anodization process by introducing oxalic acid into electrolyte while theex-situ doping involves carbon incorporation into pre-fabricated TiO2 nanotube via flame annealing using carbon blackN330. Characterization such as Scanning Electron Microscope (SEM), Energy Dispersive X-ray Analysis (EDX), and X-Ray Diffraction (XRD) are used to determine the surfacemorphology, composition of dopants, and phases exists. Well ordered nanotube with good adherence and smooth surface was obtained for both methods. When the oxide was annealed, X-ray diffraction analysis revealed the presence of anatase and rutile phase. The photocatalytic properties of thepure TiO2 and carbon doped TiO2 were tested for methyl orange degradation and the result indicated that the in-situ doped TiO2 has much better degradation than the ex-situ and pure TiO2. The percentage of methyl orange degradation for in-situ was 20% and 41% higher than ex-situ doped TiO2 and pure TiO2, respectively.

scholarly journals The Viscosity and Atomic Structure of Volatile-Bearing Melilititic Melts at High Pressure and Temperature and the Transport of Deep Carbon

Minerals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 267 ◽  
Author(s):  
Vincenzo Stagno ◽  
Veronica Stopponi ◽  
Yoshio Kono ◽  
Annalisa D’Arco ◽  
Stefano Lupi ◽  
...  
Keyword(s):  
Experimental Data ◽  
High Pressure ◽  
Atomic Structure ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
High Pressure And Temperature ◽  
X Ray ◽  
Falling Sphere ◽  
Basaltic Melts

Understanding the viscosity of mantle-derived magmas is needed to model their migration mechanisms and ascent rate from the source rock to the surface. High pressure–temperature experimental data are now available on the viscosity of synthetic melts, pure carbonatitic to carbonate–silicate compositions, anhydrous basalts, dacites and rhyolites. However, the viscosity of volatile-bearing melilititic melts, among the most plausible carriers of deep carbon, has not been investigated. In this study, we experimentally determined the viscosity of synthetic liquids with ~31 and ~39 wt% SiO2, 1.60 and 1.42 wt% CO2 and 5.7 and 1 wt% H2O, respectively, at pressures from 1 to 4.7 GPa and temperatures between 1265 and 1755 °C, using the falling-sphere technique combined with in situ X-ray radiography. Our results show viscosities between 0.1044 and 2.1221 Pa·s, with a clear dependence on temperature and SiO2 content. The atomic structure of both melt compositions was also determined at high pressure and temperature, using in situ multi-angle energy-dispersive X-ray diffraction supported by ex situ microFTIR and microRaman spectroscopic measurements. Our results yield evidence that the T–T and T–O (T = Si,Al) interatomic distances of ultrabasic melts are higher than those for basaltic melts known from similar recent studies. Based on our experimental data, melilititic melts are expected to migrate at a rate ~from 2 to 57 km·yr−1 in the present-day or the Archaean mantle, respectively.

Microstructure and Wear Properties of In Situ TiC-Cr7C3/Fe Surface Composite

2011 ◽  
Vol 415-417 ◽  
pp. 170-173
Author(s):  
Jing Wang ◽  
Si Jing Fu ◽  
Yi Chao Ding ◽  
Yi San Wang
Keyword(s):  
Sliding Wear ◽  
Wear Behavior ◽  
Wear Test ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Test Machine ◽  
Wear Properties ◽  
Surface Composite ◽  
The Matrix

A wear resistant TiC-Cr7C3/Fe surface composite was produced by cast technique and in-situ synthesis technique. The microstructure and dry-sliding wear behavior of the surface composite was investigated using scanning electron microscope(SEM), X-ray diffraction(XRD) and MM-200 wear test machine. The results show that the surface composite consists of TiC and Cr7C3as the reinforcing phase, α-Fe and γ-Fe as the matrix. The surface composite has excellent wear-resistance under dry-sliding wear test condition with heavy loads.

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