Texture on Ground, Fractured, and Aged Y-TZP Surfaces

1986 ◽  
Vol 78 ◽  
Author(s):  
Franz Reidinger ◽  
Philip J. Whalen

ABSTRACTThe phase composition of Y-TZP surfaces has been shown to vary greatly depending on the thermo-mechanical history of the surface. The orientation of these different phases in the surface region is not always random. There is speculation that the alignment of the tetragonal phase before fracturing may play a part in increasing the toughness of these materials. This article deals with an X-ray diffraction analysis of various Y-TZP surfaces with special emphasis on the texture of the different phases. Surfaces which have been ground (and polished), fractured, and aged (200°C) have been examined. In all cases, the monoclinic component that was formed was strongly oriented. The tetragonal phase may or may not be oriented depending on surface treatment. Annealing above the monoclinic-tetragonal transition temperature had little effect on the tetragonal orientation in most cases. Samples fractured at 1000°C have no unusual orientation on the fracture faces.

2019 ◽  
Vol 298 ◽  
pp. 00037 ◽  
Author(s):  
Evgeny Ageev ◽  
Anton Pereverzev

This article presents a study of the phase composition of samples sintered from isostatically pressed leaded bronze electroerosion powders obtained in distilled water. It is identified that the main phases in the sintered sample are Cu, Zn2SnO4, Pb(Cu2O2), PbO, Fe3O4.


2013 ◽  
Vol 738-739 ◽  
pp. 468-472
Author(s):  
R. Coll ◽  
J. Bonastre ◽  
J. Saurina ◽  
J.J. Suñol ◽  
L. Escoda ◽  
...  

In this work, we analyze two Mn50Ni50-xSnx alloys with Sn content i.e., x = 5 and 7.5 respectively. These alloys are produced as ribbon-shape by melt spinning. Their structural transformation is checked by calorimetry. Martensitic transformation temperatures of these alloys strongly depend on the composition. From X-ray diffraction analysis, the 14M monoclinic phase is the main phase in both alloys, but in the alloy Sn5 appears a minor tetragonal phase too.


Author(s):  
A. V. Krasikov

The processes of the formation of the nanocomposite coating of Ni–11.5% P–5%W were studied during the heat treatment of amorphous electrodeposited layers. Using the method of differential scanning calorimetry, the temperature of the onset of crystallization of the nanocrystalline phase Ni3P was determined. X-ray diffraction analysis showed that heat treatment produces Ni3P phosphides and, presumably, Ni5P2, the size of which, according to electron microscopy, is 5–50 nm. The influence of the duration of heat treatment on the phase composition and microhardness of coatings is investigated.


2012 ◽  
Vol 14 (2) ◽  
pp. 80-87 ◽  
Author(s):  
Barbara Grzmil ◽  
Bogumił Kic ◽  
Olga Żurek ◽  
Konrad Kubiak

Studies on the transformation of calcium sulphate dihydrate to hemihydrate in the wet process phosphoric acid production The influence of the process temperature from 85°C to 95°C, the content of phosphates and sulphates in the wet process phosphoric acid (about 22-36 wt% P2O5 and about 2-9 wt% SO42-) and the addition of αCaSO4·0.5H2O crystallization nuclei (from 10% to 50% in relation to CaSO4·2H2O) on the transformation of calcium sulphate dihydrate to hemihydrate has been determined. The wet process phosphoric acid and phosphogypsum from the industrial plant was utilized. They were produced by reacting sulphuric acid with phosphate rock (Tunisia) in the DH-process. The X-ray diffraction analysis was used to determine the phase composition and fractions of various forms of calcium sulphates in the samples and the degree of conversion of CaSO4·2H2O to αCaSO4·0.5H2O and CaSO4. It was found that the transformation of CaSO4·2H2O to αCaSO4·0.5H2O should be carried out in the presence of αCaSO4·0.5H2O crystallization nuclei as an additive (in the amount of 20% in relation to CaSO4·2H2O), at temperatures 90±2°C, in the wet process phosphoric acid containing the sulphates and phosphates in the range of 4±1 wt% and 27±1 wt%, respectively.


2007 ◽  
Vol 555 ◽  
pp. 59-64
Author(s):  
D. Peruško ◽  
N. Bibić ◽  
S. Petrović ◽  
M. Popović ◽  
M. Novaković ◽  
...  

The effects of nitrogen pre-implantation of AISI C1045 steel substrates on the properties of deposited TiN coatings were investigated. Nitrogen ion implantations were performed at 40 keV, to the fluences from 5x1016 – 5x1017 ions/cm2. On so prepared substrates we deposited 1.3 μm thick TiN layers by reactive sputtering. Structural characterizations of the samples were performed by grazing incidence X-ray diffraction analysis (GXRD), standard X-ray diffraction analysis (XRD), and scanning electron microscopy (SEM). Microhardness was measured by Vicker’s method. The obtained results indicate the formation of iron-nitrides in the near surface region of the substrates, more pronounced for higher implanted fluences. The structure of the deposited TiN coatings shows a strong dependence on the pre-implantation of the substrates, which is attributed to the changed local structure at the surface. Ion implantation and deposition of hard TiN coatings induce an increase of the microhardness of this low performance steel of more than eight times.


2018 ◽  
Vol 142 ◽  
pp. 03005 ◽  
Author(s):  
Peter Rusinov ◽  
Zhesfina Blednova

This paper estimated longevity and damaging of surface materials modified by alloys with thermoelastic phase transformations, taking into account: the energy consumed for the formation of failure micro-surface in one cycle, in terms of the shape of the hysteresis loop; energy intensity of the alloy, in the light of phase composition by the results of X-ray diffraction analysis. The energy intensity and theoretical strength of ternary TiNiZr systems are calculated and plotted according to thermodynamic characteristics and phase diagrams of ternary systems. This paper carried out tests of steels with surface-modified TiNiZr layers under conditions of multicyclic fatigue and frictional friction.


2020 ◽  
Vol 315 ◽  
pp. 01002 ◽  
Author(s):  
Vladimir Serebrovsky ◽  
Boris Sabel’nikov

This article presents a study of the phase composition of powder electroerosive materials of TFHA grade KNT16, obtained in ethyl alcohol. It was established that the main phases in the test sample are TiC, MoNi3, Ni, Mo.


2018 ◽  
Vol 185 ◽  
pp. 05009
Author(s):  
Maksim Anikin ◽  
Evgeniy Tarasov ◽  
Nikolay Kudrevatykh ◽  
Aleksander Zinin

In this paper the results of specific magnetization and magnetocaloric effect (MCE) measurements for Gd(Co1-xFex)2 system upon the Co substitution by Fe for the x = 0 ÷ 0.60 range are presented. Phase composition was controlled by X-ray diffraction analysis. MCE has been studied within the temperature range of 300-850 K in magnetic fields up to 17 kOe by the magnetic entropy change calculation (ΔSm). It was found that in contrast to the previously studied R(Co-Fe)2 compounds where R = Dy, Ho, Er, an ordinary symmetrical peak of ΔSm(T) in the vicinity of TC is observed for presented samples. Additionally, the MCE comparison of Gd(Co0.88Fe0.12)2 with that for the isostructural Gd(Ni0.88Fe0.12)2 compound having a plateau-like ΔSm temperature dependence is given. The obtained results are discussed.


Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4980
Author(s):  
Markus Wertz ◽  
Hieronymus Hoelzig ◽  
Gert Kloess ◽  
Sebastian Hahnel ◽  
Andreas Koenig

Background: The influence of typical manufacturing regimes for producing fixed dental prostheses (FDPs) from yttria partly-stabilized zirconia polycrystals (3Y/4Y/5Y-TZP) on the phase composition is quantified. Methods: Fixed dental prostheses (FDPs) were designed using a CAD process and machined from different Y-TZP blanks from two manufacturers differing in yttria contents. Subsequent to sintering, the FDPs were glaze fired and air-blasted using alumina particles. Phase composition was determined with X-ray diffraction and quantified with Rietveld refinement. Results: The blanks from VITA Zahnfabrik (VITA YZ HT, VITA YZ ST, VITA YZ XT) and Dental Direct (DD Bio ZX2, DD cube ONE, DD cube X2) featured a rhombohedral portion with rather small crystallites and a small monoclinic portion for 3Y/4Y-TZPs, which increased after machining and disappeared after sintering. Glaze firing and air-blasting with alumina particles had no significant influence on the phase composition. Conclusion: The phase history of dental zirconia is revealed, which may have implications on further processing and aging of the FDP (e.g. low temperature degradation) in mouth.


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