Search results for "Titan"
showing 10 items of 1109 documents
Influence of laser–target interaction regime on composition and properties of surface layers grown by laser treatment of Ti plates
2009
Surface laser treatment of commercially pure titanium plates was performed in air using two different Nd : YAG sources delivering pulses of 5 and 35 ns. The laser fluence conditions were set to obtain with each source either yellow or blue surface layers. Nuclear reaction analysis (NRA) was used to quantify the amount of light elements in the formed layers. Titanium oxinitrides, containing different amounts of oxygen and nitrogen, were mainly found, except in the case of long pulses and high laser fluence, which led to the growth of titanium dioxide. The structure of the layers was studied by x-ray diffraction and Raman spectroscopy. In addition, reflectance spectra showed the transition fr…
Harvesting rainfall energy by means of piezoelectric transducer
2013
In this paper a detailed study on the piezoelectric energy harvesting of rainfall is presented. Different features have been taken into account in order to define the limits in this energy harvesting. Only commercial transducers have been considered: a lead zirconate titanate and polyvinylidene difluoride transducer.
Comparison of spring characteristics of titanium-molybdenum alloy and stainless steel
2017
Background Titanium-molybdenum alloy (TMA) and stainless steel (SS) wires are commonly used in orthodontics as arch-wires for tooth movement. However, plastic deformation phenomenon in these arch-wires seems to be a major concern among orthodontists. This study aimed to compare the mechanical properties of TMA and SS wires with different dimensions. Material and Methods Seventy-two wire samples (36 TMA and 36 SS) of three different sizes (19×25, 17×25 and 16×22) were analyzed in vitro, with 12 samples in each group. Various mechanical properties of the wires, including spring-back, bending moment and stiffness were determined using a universal testing machine. Student’s t-test showed statis…
The multi-effects of K2TiF6 additive on the properties of PEO coatings on AZ31 Mg alloy
2020
Abstract Plasma electrolytic oxidation of AZ31 Mg alloy was performed in an alkaline silicate-based solution containing various concentrations of K2TiF6 using unipolar waveform at a constant voltage. The surface morphology of all coatings was rough and contained a micro-pore network, micro-cracks, and granules of oxide compounds in different diameters and micro-pore levels. The coating is composed of MgO, MgF2, Mg2SiO4, SiO2 (amorphous), and TiO2 (crystalline and amorphous) phases. The average thickness of the coatings was increased by adding the K2TiF6, where EDS results showed that a skinny fluoride-rich passive layer forms. With increasing time and reaching the final potential, the TiO2 …
Effect of alloy type and casting technique on the fracture strength of implant-cemented structures.
2010
Objectives: To evaluate the influence of alloy type and casting procedure on the fracture strength (FS) of metallic frameworks for implant-supported fixed prostheses. Study design: Thirty three-unit structures for lower posterior bridges were waxed-up and randomly assigned to two groups (n=15) according to alloy type and casting technique: Group 1 (C): cobalt-chromium cast in a centrifugal machine (TS1, Degussa-Hüls); Group 2 (T): titanium cast in a pressure-differential device (Cyclarc II, Morita). Each structure was cemented onto two prefabricated abutments under a constant seating pressure. After 6 months of water aging, samples were loaded in a static universal testing machine (EFH/5/FR…
Osseointegration of one-piece zirconia implants compared with a titanium implant of identical design: a histomorphometric study in the dog
2010
Objective: The aim of this study was to evaluate osseointegration of one-piece zirconia vs. titanium implants depending on their insertion depth by histomorphometry. Material and methods: Four one-piece implants of identical geometry were inserted on each side of six mongrel dogs: (1) an uncoated zirconia implant, (2) a zirconia implant coated with a calcium-liberating titanium oxide coating, (3) a titanium implant and (4) an experimental implant made of a synthetic material (polyetheretherketone). In a split-mouth manner they were inserted in submerged and non-submerged gingival healing modes. After 4 months, dissected blocks were stained with toluidine blue in order to histologically asse…
The nature of the defect structure of solid solutions based on lead zirconate titanate (PZT): Evidence from EPR and NMR
2013
The nature of intrinsic and impurity point defects in lead zirconate titanate (PZT) ceramics has been explored. Using electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) methods several impurity sites have been identified in the materials, including Fe3+-oxygen vacancy (VO) complex and Pb ions. Both of these centers are incorporated into the PZT lattice. The Fe3+-VO paramagnetic complex serves as a sensitive probe of the local crystalline field in the ceramic; the symmetry of this defect is roughly correlated with PZT phase diagram as composition is varied from PbTiO3 to PbZrO3. NMR spectra 207Pb in PbTiO3, PbZrO3 and PZT with iron content from 0 to 0.4 mol % showed t…
Luminescence of X-ray induced radiation defects in modified lithium orthosilicate pebbles with additions of titanium dioxide
2017
The authors greatly acknowledge the technical and experimental support of O. Leys, M. H. H. Kolb, and R. Knitter (Karlsruhe Institute of Technology, Germany). The work is performed in the frames of the University of Latvia financed project No. Y9-B044-ZF-N-300, “Nano, Quantum Technologies, and Innovative Materials for Economics”.
Growth of titanium oxynitride layers by short pulsed Nd:YAG laser treatment of Ti plates: Influence of the cumulated laser fluence.
2009
International audience; Titanium oxynitride layerswere formed by surface laser treatment of Ti plates in air using a Nd:YAG laser source of short pulse duration about 5 ns. The cumulated laser fluence was varied in the 100–1200 J cm2 range and its influence on the composition and the structure of the formed layers was studied by different characterization techniques providing physico-chemical and structural information. It was shown that the laser treatment induces the insertion of light elements as O, N and C in the formed layer with the amount increasing with the laser fluence. The in-depth composition of the layers and the co-existence of different phases were also studied. The way in wh…
Conductimetry and impedance spectroscopy study of low pressure metal organic chemical vapor deposition TiN O films as a function of the growth temper…
2001
Abstract Titanium oxinitride thin films have been grown by low pressure metal organic chemical vapor deposition (LP-MOCVD) using titanium isopropoxide, Ti(OCH(CH 3 ) 2 ) 4 (TIP) and NH 3 precursors in a growth temperature range from 450 to 750°C on sapphire substrates. The electrical behaviour of these films was studied between 400 and 173 K, revealing three different behaviours, ranking from a hopping conductivity (450–500°C) to a conducting one (700–750°C), with a dual behaviour for the intermediate growth temperatures. Moreover, at room temperature, both conductimetry and impedance spectroscopy highlighted a percolation behaviour, interpreted in terms of continuum percolation. The effect…