scholarly journals Corrosion Behavior of Zn, Fe and Fe-Zn Powder Materials Prepared via Uniaxial Compression

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4983
Author(s):  
Radka Gorejová ◽  
Ivana Šišoláková ◽  
Pavol Cipa ◽  
Róbert Džunda ◽  
Tibor Sopčák ◽  
...  
Keyword(s):  
Corrosion Behavior ◽  
Energy Dispersive Spectrometry ◽  
Weight Ratio ◽  
Powder Materials ◽  
Degradation Behavior ◽  
Electrochemical Polarization ◽  
Pure Zinc ◽  
Iron And Zinc ◽  
Scanning Electron ◽  
Static Immersion

Powder metallurgy is one of the most prevalent ways for metallic degradable materials preparation. Knowledge of the properties of initial powders used during this procedure is therefore of great importance. Two different metals, iron and zinc, were selected and studied in this paper due to their promising properties in the field of biodegradable implants. Raw powders were studied using scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDX). Powders (Fe, Zn and Fe-Zn in a weight ratio of 1:1) were then compressed at the pressure of 545 MPa to the form of pellets with a diameter of 1.7 cm. Surface morphology and degradation behavior in the Hanks´ solution were studied and evaluated. Electrochemical polarization tests along with the static immersion tests carried out for 21 days were employed for corrosion behavior characterization. The highest corrosion rate was observed for pure Zn powder followed by the Fe-Zn and Fe, respectively. A mixed Fe-Zn sample showed similar properties as pure zinc with no signs of iron degradation after 21 days due to the effect of galvanic protection secured by the zinc acting as a sacrificial anode.

scholarly journals Corrosion Behavior of Zinc-Graphite Metal Matrix Composite in 1 M of HCl

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
M. A. Afifi
Keyword(s):  
Corrosion Resistance ◽  
Electron Microscope ◽  
Corrosion Rate ◽  
Corrosion Behavior ◽  
Metal Matrix ◽  
Optical Microscope ◽  
Powder Metallurgy Method ◽  
Pure Zinc ◽  
Graphite Composites ◽  
Scanning Electron

This paper is aimed at investigating the corrosion behavior of Pure and Zinc-graphite particles with percentage of 1, 3, and 5%, respectively. The composites were fabricated by powder metallurgy method. Corrosion tests were performed according to ASTM standard. Corrosion rate was calculated and it is found that in all cases the corrosion rate was decreasing with the increase in exposure time. Meanwhile, the microstructure of composites was imaged and analyzed using optical microscope and scanning electron microscope. It is observed that the best corrosion resistance was zinc with 1% Graphite while Zinc with 3% and 5% Graphite composites did not enhance the corrosion resistance comparing to pure Zinc.

Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

1982 ◽  
Vol 40 ◽  
pp. 520-521
Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung
Keyword(s):  
Electron Microscopy ◽  
Corrosion Behavior ◽  
Anodic Polarization ◽  
Saline Solution ◽  
Saturated Calomel Electrode ◽  
Physiological Saline ◽  
X Ray ◽  
Physiological Saline Solution ◽  
Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

scholarly journals Analytical study of Buddha sculptures in Jingyin temple of Taiyuan, China

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Xiaojian Bai ◽  
Chen Jia ◽  
Zhigen Chen ◽  
Yuxuan Gong ◽  
Huwei Cheng ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Analytical Study ◽  
Energy Dispersive Spectrometry ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Ancient China ◽  
X Ray ◽  
Unique Style ◽  
Scanning Electron

AbstractWith exquisite design and unique style, the painted sculptures of Tutang Buddha and two attendants Buddha in Jingyin Temple are precious cultural heritages of China. The sculpture of Tutang Buddha, which was carved from a mound and painted by ancient craftsmen, was rarely found in ancient China. However, due to natural and human factors, the sculptures were severely damaged. Obviously, they require urgent and appropriate protection and restoration. In this study, samples taken from the sculptures were analysed through multiple analytical techniques, including scanning electron microscopy with energy dispersive spectrometry (SEM–EDS), Raman spectroscopy, X-ray diffraction (XRD), optical microscopy (OM) and granulometry. The analysis results enable us to infer the techniques used by the craftsmen in making the sculptures and provide a reliable evidence for the conservation and future protection of these and similar sculptures.

scholarly journals Blended PVA/PVP Electro spun nanofibers for Coating Application

2021 ◽  
Vol 2114 (1) ◽  
pp. 012031
Author(s):  
R Mohammed ◽  
H Jawad ◽  
A. Al-Zubiedy
Keyword(s):  
Electrical Conductivity ◽  
Contact Angle ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Weight Ratio ◽  
Polymeric Materials ◽  
Vinyl Pyrrolidone ◽  
Pumping Rate ◽  
Coating Application ◽  
Scanning Electron

Abstract The use of polymeric blended nanofibres is one of the recent applications in the food and liquid packaging. The current research aims to prepare the nanofibers coatings from the blend of polymeric materials via the electro spinning technique 0.08 weight ratio concentration of polyvinyl alcohol (PVA) dissolved in water, as well as, (0.2 weight ratio concentration ) of poly vinyl pyrrolidone (PVP) were used to obtain different volume proportions of (PVA:PVP) solutions include (100:0, 80:20,70:30, 50:50, 20:80, and 0:100). The electro spinning system was organized with pumping conditions (20 kV for the applied voltage, 20 cm pumping distance, 1ml/hr pumping rate) and a needle diameter with 0.4mm diameter. The properties of the polymeric solutions involve (viscosity, surface tension, and electrical conductivity of the liquid) were examined. A scanning electron microscope technique was used to study the surface properties of the prepared films, and the contact angle via the contact angle analyzer was examined. The results of a scanning electron microscope proved that the diameter of the nano fibers increases with increasing the concentration and viscosity of solutions and decreasing its electrical conductivity. Also, the results of the contact angle analyzer showed an increase the hydrophilic property via increasing percentage of polyvinylpyrrolidone.

Tribocorrosion Behaviors of D40 Steel in Artificial Seawater

2017 ◽  
Vol 898 ◽  
pp. 840-848
Author(s):  
Liang Shi ◽  
Shao Peng Qu ◽  
Hai Yan Chen ◽  
Yan Sheng Yin ◽  
Li Jing Yang
Keyword(s):  
Electron Microscopy ◽  
Oxygen Diffusion ◽  
Energy Dispersive Spectrometry ◽  
Diffusion Rate ◽  
Corrosion Process ◽  
Ion Adsorption ◽  
White Light Interferometry ◽  
Friction Process ◽  
Surface Morphologies ◽  
Scanning Electron

The friction, corrosion and tribocorrosion experiments were carried out to study the tribocorrosion characteristics of the D40 steel. Friction process was undertaken using a TriboLab. The electrochemical property of D40 steel was studied using an electrochemical workstation. The surface morphologies of the D40 steel after experiments were characterized by white light interferometry, scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results indicated that both the tribocorrosion and corrosion process of D40 steel under the condition of seawater were controlled by the cathodic oxygen diffusion. The diffusion rate of oxygen in the solution was accelerated by the friction. The phenomenon of Cl ion adsorption was more obvious for the D40 steel during tribocorrosion test, and the corrosion resistance was significantly reduced due to the promotion of friction.

Study of fossil bones by synchrotron radiation micro-spectroscopic techniques and scanning electron microscopy

2013 ◽  
Vol 21 (1) ◽  
pp. 149-160 ◽  
Author(s):  
I. M. Zougrou ◽  
M. Katsikini ◽  
F. Pinakidou ◽  
E. C. Paloura ◽  
L. Papadopoulou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cross Sections ◽  
Weight Ratio ◽  
Spectroscopic Techniques ◽  
X Ray ◽  
Osteocyte Lacunae ◽  
Fossil Bones ◽  
Bone Apatite ◽  
Scanning Electron

Earlymost Villafranchian fossil bones of an artiodactyl and a perissodactyl from the Milia excavation site in Grevena, Greece, were studied in order to evaluate diagenetic effects. Optical microscopy revealed the different bone types (fibro-lamellar and Haversian, respectively) of the two fragments and their good preservation state. The spatial distribution of bone apatite and soil-originating elements was studied using micro-X-ray fluorescence (µ-XRF) mapping and scanning electron microscopy. The approximate value of the Ca/P ratio was 2.2, as determined from scanning electron microscopy measurements. Bacterial boring was detected close to the periosteal region and Fe bearing oxides were found to fill bone cavities,e.g.Haversian canals and osteocyte lacunae. In the perissodactyl bone considerable amounts of Mn were detected close to cracks (the Mn/Fe weight ratio takes values up to 3.5). Goethite and pyrite were detected in both samples by means of metallographic microscopy. The local Ca/P ratio determined with µ-XRF varied significantly in metal-poor spots indicating spatial inhomogeneities in the ionic substitutions. XRF line scans that span the bone cross sections revealed that Fe and Mn contaminate the bones from both the periosteum and medullar cavity and aggregate around local maxima. The formation of goethite, irrespective of the local Fe concentration, was verified by the FeK-edge X-ray absorption fine structure (XAFS) spectra. Finally, SrK-edge extended XAFS (EXAFS) revealed that Sr substitutes for Ca in bone apatite without obvious preference to the Ca1or Ca2unit-cell site occupation.

Homogenization Treatment to Optimize the Microstructures of the Al-3.5Cu-1.5Li Alloy and Analysis of Al3Zr Precipitates

2018 ◽  
Vol 921 ◽  
pp. 195-201 ◽  
Author(s):  
Jin Jun Xu ◽  
Mang Jiang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Energy Dispersive Spectrometry ◽  
Single Step ◽  
Experimental Alloy ◽  
Composition Distribution ◽  
Double Step ◽  
Homogenization Treatment ◽  
Transmission Electron ◽  
Scanning Electron

The microstructure evolution and composition distribution of the cast Al-3.5Cu-1.5Li-0.11Zr alloy during single-step and double-step homogenization were studied with the help of the optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM) methods. The results show that severe dendrite segregation exists in the experimental alloy. Six different homogenization treatments, conventional one-stage homogenization and double-stage homogenization are carried out, and the best homogenization treatment of the experimental alloys was achieved. Moreover, the precipitation of Al3Zr particles was significantly different after two kinds of homogenization in the experimental alloy. Compared with the single-stage homogenization, a finer particle size and distribution more diffuse of Al3Zr particles can be obtained in the double-stage homogenization treatment.

scholarly journals Microstructure and Corrosion Behavior of Friction Stir-Welded 6061 Al/AZ31 Mg Joints with a Zr Interlayer

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1115 ◽  
Author(s):  
Yang Zheng ◽  
Xiaomeng Pan ◽  
Yinglei Ma ◽  
Shuming Liu ◽  
Libin Zang ◽  
...  
Keyword(s):  
Corrosion Behavior ◽  
Galvanic Corrosion ◽  
Stir Zone ◽  
Thermal Barrier ◽  
Al Alloy ◽  
X Ray ◽  
Friction Stir ◽  
Base Materials ◽  
Dissimilar Alloys ◽  
Scanning Electron

Friction stir welding (FSW) with a Zr interlayer was employed to join dissimilar alloys of 6061 Al and AZ31 Mg. The microstructures of Al/Mg and Al/Zr/Mg joints were investigated by optical microscopy (OM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometer (EDS). The results showed that the central part of the Zr interlayer was smashed and intermixed with the base materials in the stir zone, whereas the undamaged part remained stable at the Al/Mg interface. The formation of Al–Mg intermetallic compounds (IMCs) was suppressed by the Zr interlayer due to its synergetic effects of chemical modification and thermal barrier. The electrochemical measurements revealed a differentiated corrosion behavior for each joint, where the corrosion rate of representative regions increased in the order of Al alloy < Mg alloy < heat-affected zone < stir zone. The immersion tests indicated an enhancement in corrosion resistance for the Al/Zr/Mg joint compared with the Al/Mg joint, which is owing to the mitigated galvanic corrosion between the base materials by the Zr interlayer.

Effect of Anthracite on Preparation of Ceramsite Using Red Mud

2013 ◽  
Vol 467 ◽  
pp. 3-7
Author(s):  
Hui Fen Yang ◽  
Lin Fei Lu ◽  
Bei Ping Jiang ◽  
Jin Long Zhang
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Scanning Electron Microscopy ◽  
Bulk Density ◽  
Red Mud ◽  
Absorption Rate ◽  
Weight Ratio ◽  
Foaming Agent ◽  
Thermal Stability Of ◽  
Scanning Electron

Based on analyzing of chemical composition, mineral composition and thermal stability of red mud, preparation of ceramisite, using anthracite added as foaming agent, was investigated. Internal structure was observed by scanning electron microscopy (SEM). The results showed the bulk density of ceramisite was obviously reduced by anthracite added. The ceramisite with bulk density of 1.30g/cm3, water absorption rate£ ̈WAR£©of 2.98% and cylinder compressive strength £ ̈CCS£©of 9.48 MPa was obtained when weight ratio of red mud/waste glass/bentonites/anthracite was at 73:15:11:1. Majority of porosity in ceramisite was closed based on SEM. The porosity of ceramisite was much higher when anthracite was added as foaming agent than only calcite in red mud was used as foaming agent. The bulk density of the former was lower than that of the latter.

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