DTA Analysis on the Solidification Behavior of the Al2O2-Y2O3-ZrO2 Ternary Oxide System and Microstructural Investigation

2012 ◽  
Vol 706-709 ◽  
pp. 2424-2427
Author(s):  
Hai Jun Su ◽  
Jun Zhang ◽  
Wei Guo ◽  
Jian Zheng Yu ◽  
Lin Liu ◽  
...  
Keyword(s):  
Heating Temperature ◽  
Solidus Temperature ◽  
Ternary Eutectic ◽  
Eutectic Structure ◽  
Oxide System ◽  
Ternary Oxide ◽  
Oxide Ceramic ◽  
Solidification Behavior ◽  
Microstructural Investigation ◽  
Dta Analysis

The well-aligned growth structures which derive from directional solidification of ceramic eutectics are of great interests due to their potential use in electronic devices and as structural materials at high temperatures. Because of the complexity of the component system and very high melting points, the solidification behavior on the oxide ceramic eutectic is still unclear up to date. In the presented paper, the Al2O3-Y2O3-ZrO2ternary eutectic ceramic is remelted by a DTA apparatus. The maximal heating temperature is 1950 °C. The melting and solidification behavior are investigated by the DTA analysis. The solidification microstructure is investigated by scanning electron microscopy (SEM), energy disperse spectroscopy (EDS) and X-ray diffraction (XRD). The results show that solidus temperature and the liquidus temperature are 1738.4 °C and 1750.1 °C, respectively. The formation path of eutectic phase is discussed. The microstructure of as-solidified eutectic ceramic shows a divorced ternary eutectic structure consisting of Al2O3, YAG and ZrO2phases with a random distribution. Furthermore, the microstructural comparison with directionally solidified ternary eutectic ceramic is presented and discussed.

Thermal Properties of Cu-Hf-Ti Metallic Glass Compositions

2012 ◽  
Vol 1485 ◽  
pp. 155-160 ◽  
Author(s):  
I. A. Figueroa
Keyword(s):  
Liquidus Temperature ◽  
Composition Range ◽  
Solidus Temperature ◽  
Ternary Eutectic ◽  
Alloy System ◽  
Glassy Alloys ◽  
Wide Range ◽  
Compositional Field ◽  
Dta Analysis ◽  
Glass Compositions

ABSTRACTThe glass transition temperature Tg, crystallization temperature Tx, solidus temperature Tm, and liquidus temperature Tl, of a number of ternary Cu-Hf-Ti glassy alloys in the composition range of 51< Cu <67, 5 < Hf < 40 and 5 < Ti <40 (at.%) are reported and discussed. It is found that increasing the Ti:Hf ratio results in a rapid decreasing of Tg and Tx. This behavior is related to the fact that the melting point and cohesive energy for Ti are substantially lower than for Hf. The solidus temperature Tm, remains relatively constant on a wide range of compositions. The liquidus temperatures data suggest a ternary eutectic within the compositional field encompassed by the Cu55Hf20Ti25, Cu59Hf21Ti20, Cu60Hf20Ti20 and Cu55Hf21Ti24 alloys, with a liquidus temperature, Tl, of ∼1170 K; this is supported by the DTA traces, which show a single melting peak. Based on the DTA analysis, the experimentally calculated liquidus projection for the ternary Cu-Hf-Ti alloy system is also reported.

Solidification of Eutectic Bi32.5In51Sn16.5 Alloy under Microgravity Using a Drop Tube

2010 ◽  
Vol 660-661 ◽  
pp. 587-592 ◽  
Author(s):  
Rafael Cardoso Toledo ◽  
M.B. Mattos ◽  
Chen Y. An ◽  
I.N. Bandeira
Keyword(s):  
Ternary Eutectic ◽  
Space Station ◽  
Eutectic Structure ◽  
Security Requirements ◽  
Drop Tube ◽  
Eutectic Melting ◽  
Irregular Structures ◽  
Microgravity Conditions ◽  
Free Solder ◽  
Containerless Solidification

Containerless solidification of Bi32.5In51Sn16.5 eutectic alloy under microgravity conditions was investigated by using a 3 m length drop tube. The Bi-In-Sn system is an important material for lead-free solder and fuse element for electrical protection. It has a low eutectic melting temperature of 60°C, which is suitable for experiments in restricted environments like the International Space Station (ISS), where the security requirements are very strict. Droplets, with diameters in the range of 200 to 400 m, solidified under microgravity, were obtained consistently with irregular ternary eutectic structure, whereas, previous results under normal gravity presented both regular lamellar and irregular structures.

scholarly journals Electronic properties of the Sn1−xPbxO alloy and band alignment of the SnO/PbO system: a DFT study

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
N. Kelaidis ◽  
S. Bousiadi ◽  
M. Zervos ◽  
A. Chroneos ◽  
N. N. Lathiotakis
Keyword(s):  
Band Gap ◽  
Electronic Properties ◽  
Density Functional ◽  
Hydrogen Generation ◽  
Valence Band Maximum ◽  
Oxide System ◽  
Band Alignment ◽  
Oxide Thin Film ◽  
Ternary Oxide ◽  
P Type

Abstract Tin monoxide (SnO) has attracted attention due to its p-type character and capability of ambipolar conductivity when properly doped, properties that are beneficial for the realization of complementary oxide thin film transistors technology, transparent flexible circuits and optoelectronic applications in general. However, its small fundamental band gap (0.7 eV) limits its applications as a solar energy material, therefore tuning its electronic properties is necessary for optimal performance. In this work, we use density functional theory (DFT) calculations to examine the electronic properties of the Sn1−xPbxO ternary oxide system. Alloying with Pb by element substitution increases the band gap of SnO without inducing defect states in the band gap retaining the anti-bonding character of the valence band maximum which is beneficial for p-type conductivity. We also examine the properties of the SnO/PbO heterojunction system in terms of band alignment and the effect of the most common intrinsic defects. A broken gap band alignment for the SnO/PbO heterojunction is calculated, which can be attractive for energy conversion in solar cells, photocatalysis and hydrogen generation.

A novel Zr-Ti-Ni-Cu eutectic system with low melting temperature for the brazing of titanium alloys near 800 °C

2010 ◽  
Vol 25 (2) ◽  
pp. 296-302 ◽  
Author(s):  
Ju-Hyun Sun ◽  
Dong-Myoung Lee ◽  
Chi-Hwan Lee ◽  
Joo-Wha Hong ◽  
Seung-Yong Shin
Keyword(s):  
Melting Temperature ◽  
Eutectic Alloy ◽  
Ternary Eutectic ◽  
Pure Titanium ◽  
Alloy System ◽  
Eutectic Structure ◽  
Eutectic System ◽  
Alloy Sample ◽  
Commercially Pure Titanium ◽  
Cu Content

This article reports on low (below 800 °C) melting temperature characteristics of a Zr-Ti-Ni-Cu alloy system, designed by adding a small amount of Cu to a Zr-Ti-Ni eutectic alloy system in the Zr-rich corner of the Zr-Ti-Ni system. A series of Zr-Ti-Ni-Cu-based alloy buttons of varying Cu content was fabricated by an arc melting machine. The melting temperature ranges of the quaternary alloys were systematically examined by differential thermal analysis (DTA). As a result, a quaternary eutectic alloy of composition Zr54Ti22Ni16Cu8 with a low melting temperature range from 774 °C to 783 °C was found. In addition, structural and chemical analysis results for the slowly solidified, quaternary eutectic alloy sample revealed equivalent quaternary eutectic structure and phases to those of the ternary eutectic Zr50Ti26Ni24 alloy, except for a small amount of Cu dissolved in individual constituent phases. The wetting angle tested at 800 °C for 60 s on the commercially pure titanium was about 25°.

scholarly journals Effect of Oxide Scale on Hot Dip Zn-Al-Mg Alloy Coating Prepared by Reduction Combined with Induction Heating

Metals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1519
Author(s):  
Yijie Zhang ◽  
Minyun Xu ◽  
Ruina Ma ◽  
An Du ◽  
Yongzhe Fan ◽  
...  
Keyword(s):  
Oxide Scale ◽  
Surface Quality ◽  
Induction Heating ◽  
Ternary Eutectic ◽  
Alloy Coating ◽  
Eutectic Structure ◽  
Scale Thickness ◽  
Rapid Induction ◽  
Fe4al13 Phase

Hot dipping Zn-Al-Mg coatings were prepared by rapid induction heating combined with gas protection. The influence of oxide scale on the structure and surface quality of a hot-dip Zn-6Al-3Mg alloy coating was studied in this paper. The results showed that the reaction of Fe-Al was suppressed by the scale on the surface of the steel plate. When the thickness of scale was 10 μm and the steel entry temperature was 900 °C, the surface quality of the coating was good. The Zn-Al-Mg coatings mainly consisted of the ternary eutectic structure of Zn/Al/MgZn2 and Fe4Al13 at the interface. When the scale thickness was 2–3 μm with the same steel entry temperature, the surface quality of the coating was poor, and serious stripe-like protrusion defects were formed on the surface of the coating, which was mainly caused by the Fe4Al13 phase separating from the substrate / coating interface into the overlay.

Synthesis and characterization of cordierite from acetylacetonate/alkoxide precursors

1993 ◽  
Vol 8 (7) ◽  
pp. 1697-1702 ◽  
Author(s):  
Lawrence D. David ◽  
Ronald M. Anderson ◽  
Joseph M. Dynys ◽  
Charles C. Goldsmith ◽  
Andrew Szule
Keyword(s):  
Primary Particle ◽  
Oxide System ◽  
Ethanol Solution ◽  
Ternary Oxide ◽  
Alkyl Esters ◽  
Α Phase ◽  
Alkoxide Precursors ◽  
Ternary Oxide System ◽  
Spray Dried

Syntheses of ultrafine glass powders in the MgO–Al2O3–SiO2 ternary oxide system were effected by drying and calcining sols derived from acetylacetonate-tetraethoxysilane ethanol solutions. A mixture of magnesium and aluminum acetylacetonates, dissolved with Si(OC2H5)4 in an ethanol solution in a 2:4:5 Mg: Al: Si mole ratio, was hydrolyzed, spray-dried, and calcined to yield a glass powder of 70 Å primary particle size, which sintered to densities ≥ 2.5 g/cm3 and which formed μ-cordierite as the only crystalline phase below 1000 °C. Incorporation of dopant quantities of boron and phosphorus, via their alkyl esters in the hydrolysis reaction with Si(OC2H5)4 and the acetylacetonates, afforded powders which crystallized in the α-phase directly after sintering to density = 2.66 g/cm3.

scholarly journals A tunable amorphous p-type ternary oxide system: The highly mismatched alloy of copper tin oxide

2015 ◽  
Vol 118 (10) ◽  
pp. 105702 ◽  
Author(s):  
Patrick J. M. Isherwood ◽  
Keith T. Butler ◽  
Aron Walsh ◽  
John M. Walls
Keyword(s):  
Tin Oxide ◽  
Oxide System ◽  
Ternary Oxide ◽  
P Type ◽  
Ternary Oxide System

Microstructural evolution in lead-free solder alloys: Part I. Cast Sn–Ag–Cu eutectic

2004 ◽  
Vol 19 (5) ◽  
pp. 1417-1424 ◽  
Author(s):  
Sarah L. Allen ◽  
Michael R. Notis ◽  
Richard R. Chromik ◽  
Richard P. Vinci
Keyword(s):  
Effective Activation Energy ◽  
Ternary Eutectic ◽  
Eutectic Structure ◽  
Lead Free ◽  
Lead Free Solder ◽  
Solder Alloys ◽  
Controlling Mechanism ◽  
Coarsening Kinetics ◽  
Free Solder

Coarsening of the ternary eutectic in cast Sn–Ag–Cu lead-free solder alloys was investigated. The process was found to follow r3 ∝ t kinetics where r is the rod radius of the dispersed phase and t is time. The effective activation energy for the process is 69 ± 5 kJmol-1. The two types of intermetallic rods, Cu6Sn5 and Ag3Sn, in the eutectic structure coarsen at different rates, with each having a different rate-controlling mechanism. The overall coarsening kinetics for the Sn–Ag–Cu ternary eutectic is significantly slower than that found for the Pb-Sn eutectic, which has implications for long-term reliability of Sn–Ag–Cu solder joints.

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