Nondestructive Characterization of Beryllium Effects on Ni-Cr Dental Alloy Elastic Properties and Microstructure: Ultrasonics, X-Ray Diffractometry, Scanning Electron Microscopy and Wavelength Dispersive Spectrometry

1988 ◽  
Vol 142 ◽  
Author(s):  
Surendra Singh ◽  
J. Lawrence Katz ◽  
B. S. Rosenblatt

AbstractKnowledge of structure-properties relationship is a key factor in the development and improvement of new and existing metal alloys through manipulation in their chemical-compositions. In this study, the elastic properties and microstructure of cast Ni-Cr-Be and Ni-Cr dental alloys were studied. The elastic properties, i.e., Young's, shear and bulk moduli and Poisson's ratios, were determined using measurements on the ultrasonic velocities and densities. Both the shear and the longitudinal (dilatational) velocities were measured using an ultrasonic pulse-through-transmission method; density was measured using a buoyant force method. In microstructure, crystallinity, porosity, particle-size and quantitative elemental compositions were studied using x-ray diffractometry (XRD), scanning electron microscopy (SEM) and wavelength dispersive spectrometry (WDS) respectively. These results show that: (1) the addition of Be increased significantly the alloy's elastic moduli and Poisson's ratio; and (2) the presence of Be in Ni-Cr alloy also significantly modified its microstructure by producing a second binary phase, Ni-Be, in eutectic areas.

2008 ◽  
Vol 368-372 ◽  
pp. 1143-1145 ◽  
Author(s):  
Ding Fan ◽  
Yao Ning Sun ◽  
Min Zheng ◽  
Jian Bin Zhang ◽  
Yu Feng Zheng

Laser cladding experiment was carried out with a 5 kW continuous wave CO2 laser by preplacing Ni75Si25 and Ni78Si13Ti9 powders onto Ni-based superalloy substrate. The microstructure of the specimens was monitored by using optical and scanning electron microscopy. The chemical compositions of the alloys and their phases were obtained using X-ray diffraction and energy dispersive x-ray spectroscopy. The phase transformation temperatures were determined by non-isothermal differential scanning calorimetry tests. The microhardness of the laser cladded sample was measured.


2016 ◽  
Vol 872 ◽  
pp. 211-215 ◽  
Author(s):  
Pusit Pookmanee ◽  
Atit Wannawek ◽  
Sakchai Satienperakul ◽  
Ratchadapon Putharod ◽  
Nattapol Laorodphan ◽  
...  

This research studies compositions of diatomite, leonardite and pumice for utilization appropriate to the properties of materials. Chemical compositions of these materials were characterized by X–ray fluorescence spectrometry (XRF) and energy dispersive X–ray spectrometry (EDXS). The silica was major component of these materials. The morphology was investigated by scanning electron microscopy (SEM). Diatomite was cylindrical in shape, leonardite was sheet or flake in shape and pumicewas prismatic in shape. The structure was studied by X–ray diffraction (XRD). It was found that the mineral composition of diatomite, leonardite and pumice showed cristobalite low, quartz and anorthite, respectively. The functional groups were identified by Fourier transform infraredspectrometry (FTIR). The functional group of siloxane was obtained and dominated vibration in these materials. And the vibration of carboxylic, alcoholic and carbonyl groups were obtained in leonardite.


2012 ◽  
Vol 621 ◽  
pp. 48-53
Author(s):  
Yan Ping Liu ◽  
Jiang Tao Zhang ◽  
Xiao Ya Luo ◽  
Ying Ying Yao

The micro/nanofibrils of poplar could be prepared by treatment of ultrasonic. The properties of micro/nanofibrils were characterized by using scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The results indicated that poplar micro/nanofibril was the same as raw fiber in chemical compositions and crystal structure. The crystallinity of micro/nanofibrils was 84.99 percent, increased by 20 percent compared to original fiber after ultrasonic crushing. The micro/nanofibril diameter was from 50 nm to 1 μm.The internal bond strength (IB) of wheat-straw fiberboard could be significantly improved by adding poplar micro/nanofibril suspension to the urea formaldehyde resin adhesive(UF),when the adding amount of poplar micro/nanofibril suspension was 15wt percent, the IB of wheat-straw fiberboard was up to 0.86 MPa.


2008 ◽  
Vol 591-593 ◽  
pp. 879-884 ◽  
Author(s):  
Lia Maria Carlotti Zarpelon ◽  
Eliner Affonso Ferreira ◽  
Hidetoshi Takiishi ◽  
Rubens Nunes de Faria Jr.

Microstructures and chemical compositions of some commercial La-Mg based alloys have been investigated. The hydrogen storage alloys can be represented by the formulae La2Mgx, La2Mgx-1Ni and LaMg2Ni9 (x=12 or 17). The determination of the microstructures and phase compositions of these alloys has been carried out using scanning electron microscopy and energy dispersive X-ray analysis.


2019 ◽  
Vol 3 (3) ◽  
pp. 51-56
Author(s):  
Remigiusz Romankiewicz ◽  
Ferdynand Romankiewicz

The influence of the chemical composition of selected armature brasses on the formation of hard inclusions was investigated. In metallographic studies using optical microscopy and scanning electron microscopy with X-ray microanalysis (EDS), it was found that hard inclusions attain sizes ranging from several hundred nanometers to several micrometers. Investigations of samples that were taken from metallurgical pigs of armature brass of various chemical compositions have shown that the contribution of components such as iron and silicon have a decisive influence on the formation of hard inclusions. These components have a dominant share in hard inclusions (60–76 wt.% Fe and 10.6–17.4 wt.% Si). In much smaller quantities there are also elements such as manganese, phosphorus, nickel and chromium. The chemical composition of hard inclusions varies. The number and size of hard inclusions depends on the contribution of iron and silicon brass. In the brass sample with 0.31 wt.% Fe and 0.08 wt.% Si, 1183 inclusions per square millimeters were identified, while in the brass sample with 0.21 wt.% Fe and 0.11 wt.% Si the amount of hard inclusions was reduced to 933 inclusions per square millimeters. In the brass sample with reduced iron content up to 0.08 wt.% and silicon up to 0.006 wt.%, no hard inclusions were identified.


2012 ◽  
Vol 506 ◽  
pp. 425-428 ◽  
Author(s):  
Pusit Pookmanee ◽  
P. Thippraphan ◽  
P. Jansanthea ◽  
Sukon Phanichphant

Natural diatomite was modified by manganese chloride via the low temperature hydrothermal route. The chemical properties and adsorption efficiency of the natural and the modified diatomite were characterized. The chemical compositions of the natural and the modified diatomite were determined by X-ray fluorescence spectroscopy (XRF) and energy dispersive X-ray spectrometry (EDXS). Morphology of the natural and the modified diatomite was investigated by scanning electron microscopy (SEM). The adsorptions of Cd (II) and Pb (II) ions onto the natural and the modified diatomite were determined by atomic absorption spectroscopy (AAS).


2014 ◽  
Vol 804 ◽  
pp. 139-142
Author(s):  
Kyung Nam Kim ◽  
Sung Jin Kim

In this study, the characteristics of porcelain body, glaze and inlay were analyzed, using Koryo celadon shard of 10th-14thcentury. The characterization of celadon shard were investigated by Scanning electron microscopy, X-ray fluriscence, X-ray diffractometer, and Dilatometer. The characteristics of celadon shard is similar in color to gray-green with the naked eye, and the thickness of glaze layer and body is about 149.5-200μm and 4.2-8.8mm. The chemical compositions of body is SiO270.9-74.8wt%, Al2O319.4-20.5wt%, RO▪RO2(R=Ca, Mg, K) 4.0-7.0wt% and Fe2O31.3-2.7wt% in weight ratio. The high contents (12.5-24.6wt%) of calcium oxide in the glaze is considered lime type. In the chemical compositions of the white and black inlay Al2O3is 33.2-37.1wt% and 19.7wt%, and Fe2O3is 1.1wt% and 5.6wt% in weight ratio, respectively. The density of black inlay is higher than that of white inlay, and firing temperature for celadon may be about 1250°C.


Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.


Author(s):  
M. L. Zimny ◽  
A. C. Haller

During hibernation the ground squirrel is immobile, body temperature reduced and metabolism depressed. Hibernation has been shown to affect dental tissues varying degrees, although not much work has been done in this area. In limited studies, it has been shown that hibernation results in (1) mobilization of bone minerals; (2) deficient dentinogenesis and degeneration of alveolar bone; (3) presence of calculus and tears in the cementum; and (4) aggrevation of caries and pulpal and apical tooth abscesses. The purpose of this investigation was to study the effects of hibernation on dental tissues employing scanning electron microscopy (SEM) and related x-ray analyses.


Author(s):  
Yun Lu ◽  
David C. Joy

High resolution scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDXA) were performed to investigate microparticles in blended cements and their hydration products containing sodium-rich chemical wastes. The physical appearance of powder particles and the morphological development at different hydration stages were characterized by using high resolution SEM Hitachi S-900 and by SEM S-800 with a EDX spectrometer. Microparticles were dispersed on the sample holder and glued by 1% palomino solution. Hydrated bulk samples were dehydrated by acetone and mounted on the holder by silver paste. Both fracture surfaces and flat cutting sections of hydrating samples were prepared and examined. Some specimens were coated with an 3 nm thick Au-Pd or Cr layer to provide good conducting surfaces. For high resolution SEM S-900 observations the accelerating voltage of electrons was 1-2 KeV to protect the electron charging. Microchemical analyses were carried out by S800/EDS equipped with a LINK detector of take-off angle =40°.


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