Effect of Cooling Velocity and Casting Temperature on Solidification Microstructure of Pure Al Refinement under Al-5Ti-B Alloy

2013 ◽  
Vol 477-478 ◽  
pp. 1316-1320
Author(s):  
Wan Wu Ding ◽  
Xin Zhao ◽  
Fu Liang Zhu ◽  
Tian Dong Xia ◽  
Wen Jun Zhao
Keyword(s):  
Cooling Rate ◽  
Molten Aluminum ◽  
Pure Aluminum ◽  
Texture Feature ◽  
Solidification Microstructure ◽  
Solidification Structure ◽  
Casting Temperature ◽  
X Ray Diffraction ◽  
Equiaxial Crystal ◽  
Cooling Velocity

The texture feature and grain refinement effect of Al-5Ti-B alloy on pure aluminum were analyzed and by adjusting the cooling velocity and casting temperature of molten aluminum,the influence of Al-5Ti-B alloy on solidification microstructure of pure aluminum was studied by using X-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy (OM) and other experimental methods. The results show that: Al-5Ti-B alloy is composed of Al, TiAl3 and TiB2. under the same solidified velocity,with the increase of the mass fraction of Al-5Ti-B alloy among the aluminum melt, solidification structure of pure aluminum equiaxed dendrite size small. But at the same additives of Al-5Ti-B alloy, the cooling rate and casting temperature have significant effects on the number and size of equiaxial crystal. Faster cooling rate and lower casting temperature of molten aluminum are favorable for the formation of thin equiaxial crystal of solidification microstructure.

scholarly journals A Precipitation Phenomenon of Titanium Compounds in Aluminum Melts and the Refinement Fading Mechanism of the Al-5Ti-0.62C Master Alloy

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Wanwu Ding ◽  
Wenjun Zhao ◽  
Tiandong Xia
Keyword(s):  
Electron Microscopy ◽  
Master Alloy ◽  
Molten Aluminum ◽  
Pure Aluminum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Commercially Pure ◽  
Titanium Compounds ◽  
Refinement Effect ◽  
Scanning Electron

The Al-5Ti-0.62C master alloy was prepared through a method of thermal explosion in molten aluminum. The process of remelting and refining of commercially pure aluminum was conducted, and precipitation samples with different heat-treatment times were obtained. Scanning electron microscopy (SEM), X-ray diffraction (XRD), optical microscopy (OM), and other techniques were used to analyze the microstructure of the precipitates at the bottom of the samples so as to explore the fading mechanism of Al-Ti-C alloy refinement. The results showed that an obvious precipitation phenomenon of titanium compounds existed in the remelted Al-5Ti-0.62C master alloy and that there were both TiC compounds and TiAl3compounds in the precipitates; in the refined pure aluminum samples, the precipitates were mainly TiC compounds. Precipitation of titanium compounds in aluminum melting is the main cause of fading in the refinement effect of an Al-Ti-C master alloy.

Study on Hydrogen Content of Solid Industrial Pure Aluminum

2014 ◽  
Vol 633-634 ◽  
pp. 129-132
Author(s):  
Bei Huang ◽  
Jian Min Zeng ◽  
Li Hua Liang ◽  
Wu Kui Gan ◽  
Jin Bo Lu
Keyword(s):  
Cooling Rate ◽  
Hydrogen Content ◽  
Molten Aluminum ◽  
Pure Aluminum ◽  
Optical Microscope ◽  
Solid Aluminum ◽  
Long Time

The hydrogen contents of molten aluminum solidifying in various molds were tested by the use of the G4 Phoenix DH and the samples of microstructure were analyzed under the optical microscope (OM). The results show that the hydrogen contents of solid aluminum decreases with the decreasing cooling rate. However, when molten aluminum solidifies in the adiabatic mold, the hydrogen content has a slight increase because of long time of exposure to the air. In addition, the microstructure of casting pure aluminum is refined with increasing cooling rate.

Research on Grain Refinement Effect of Al-5Ti-C Alloy on Pure Aluminum and its Attenuation Mechanism

2013 ◽  
Vol 477-478 ◽  
pp. 1293-1297
Author(s):  
Wan Wu Ding ◽  
Tian Dong Xia ◽  
Jiang Tao Zhu ◽  
Wen Jun Zhao ◽  
Yang Tao Xu
Keyword(s):  
Grain Refinement ◽  
Pure Aluminum ◽  
Texture Feature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Commercially Pure ◽  
Titanium Compound ◽  
Attenuation Mechanism ◽  
Heat Preservation ◽  
Refinement Effect

The texture feature and grain refinement effect of Al-5Ti-C alloy on pure aluminum were analyzed and its attenuation mechanism was discussed by using X-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy (OM) and other experimental methods.The results show that: Al-5Ti-C alloy is composed of Al, TiAl3 and TiC. Al-5Ti-C alloy has a good grain refining capacity for commercially pure aluminum. During the heat preservation process, due to precipitation of titanium compound in the aluminum melt, refinement effect of Al-Ti-C alloy is declined.

Texture and Microstructure Effects on Electromigration Behavior of Aluminum Metallization

1991 ◽  
Vol 225 ◽  
Author(s):  
D. B. Knorr ◽  
K. P. Rodbell ◽  
D. P. Tracy
Keyword(s):  
Grain Size ◽  
Standard Deviation ◽  
Pure Aluminum ◽  
Time To Failure ◽  
X Ray Diffraction ◽  
Aluminum Films ◽  
Failure Data ◽  
Transmission Electron ◽  
Aluminum Metallization ◽  
Microstructure Effects

ABSTRACTPure aluminum films are deposited under a variety of conditions to vary the crystallographic texture. After patterning and annealing at 400°C for 1 hour, electromigration tests are performed at several temperatures. Failure data are compared on the basis of t50 and standard deviation. Microstructure is quantified by transmission electron microscopy for grain size and grain size distribution and by X-ray diffraction for texture. A strong (111) texture significantly improves the electromigration lifetime and decreases the standard deviation in time to failure. This improvement correlates with both the fraction and sharpness of the (111) texture component.

Phase Formation in FeOx-SiO2-Cu2O-ZnO-FeS System during Melts Crystallization

2010 ◽  
Vol 297-301 ◽  
pp. 602-607
Author(s):  
Evgeny N. Selivanov ◽  
R.I. Gulyaeva ◽  
N.I. Selmenskich
Keyword(s):  
Cooling Rate ◽  
Phase Formation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Two Samples ◽  
And Calorimetry

The phase formation in oxide-sulphidic systems was studied with the use of X-ray diffraction, mineralography, combined thermogravimetry and calorimetry, in addition to Х-ray spectral microanalysis. The purpose of this work was to estimate the effect of cooling rate of melts in FeOx-SiO2-Cu2O-ZnO-FeS systems on structure and content of the resulting phases. Test subjects were two samples having following compositions (wt. %): I - 40.5 Fe, 2.41 S, 0.87 Cu, 3.87 Zn, 32.1 SiO2 and II - 40.7 Fe, 3.05 S, 8.55 Cu, 4.1 Zn and 19.5 SiO2. Cooling rate of the melts was changed from 0.3 up to 900оС/s.

The Formation Mechanism of Equiaxed Crystals in Pure Aluminum Solidification Structure under the Al-Ti-C Master Alloy

2013 ◽  
Vol 668 ◽  
pp. 865-869
Author(s):  
Wan Wu Ding ◽  
Wen Jun Zhao ◽  
Tian Dong Xia
Keyword(s):  
Transition Zone ◽  
Formation Mechanism ◽  
Master Alloy ◽  
Heterogeneous Nucleation ◽  
Pure Aluminum ◽  
Solidification Structure ◽  
Impact Mechanism ◽  
Tic Particle ◽  
The Impact

The influence of different solidified velocities on the structure of pure aluminum during the process of refinement by Al-5Ti-0.6C master alloy was studied and the impact mechanism was discussed. The results show that at the same solidified velocity, with the increase of the amount of Al-5Ti-0.6C master alloy, in the solidified structure of pure aluminum, columnar crystals will gradually decrease, while equiaxed crystals will gradually increase. But in the case when the level of addition is the same, the faster the solidified velocity, the greater the number of equiaxed crystals will be in the ingot microstructure. The formation of equiaxed crystals is the result of the dual role of dissociation of crystal particles and heterogeneous nucleation of “TiC particle---Ti transition zone”.

scholarly journals The Development of Rapidly Solidified Magnesium – Copper Ribbons

2016 ◽  
Vol 61 (2) ◽  
pp. 1083-1088
Author(s):  
M. Pastuszak ◽  
G. Cieślak ◽  
A. Dobkowska ◽  
J. Mizera ◽  
K.J. Kurzydłowski
Keyword(s):  
Corrosion Resistance ◽  
Cooling Rate ◽  
Melt Spinning ◽  
Diffraction Method ◽  
Electrode System ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Copper Addition ◽  
Rapidly Solidified ◽  
Thermal Stability Of

Abstract The aim of the present work was to plan and carry out an experiment consisting of amorphization of industrial magnesium alloy WE 43 (Mg - 4 Y - 3 RE - 0.5 Zr) modified by the copper addition. Investigated alloy modified with 20% of copper was rapidly quenched with the use of melt spinning technique. The effects of cooling rate on the structure and properties of the obtained material were extensively analyzed. The structure and phase analysis of samples were examined using X-ray diffraction method (XRD) while the thermal stability of the samples was determined by differential scanning calorimetry (DSC). Microstructure observations were also conducted. The microhardness tests (HV0.02) and corrosion resistance tests were carried out to investigate the properties of the material. Corrosion resistance measurements were held using a typical three-electrode system. As the result of the research, the effect of cooling rate on microstructure and properties of investigated alloy was determined.

Effects of Cooling Rate and Sn Addition on the Microstructure of Ti-Nb-Sn Alloys

2011 ◽  
Vol 172-174 ◽  
pp. 190-195 ◽  
Author(s):  
Giorgia T. Aleixo ◽  
Eder S.N. Lopes ◽  
Rodrigo Contieri ◽  
Alessandra Cremasco ◽  
Conrado Ramos Moreira Afonso ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cooling Rate ◽  
Melting Furnace ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Β Phase ◽  
Arc Melting ◽  
Ti Alloys ◽  
Ω Phase

Ti-based alloys present unique properties and hence, are employed in several industrial segments. Among Ti alloys, β type alloys form one of the most versatile classes of materials in relation to processing, microstructure and mechanical properties. It is well known that heat treatment of Ti alloys plays an important role in determining their microstructure and mechanical behavior. The aim of this work is to analyze microstructure and phases formed during cooling of β Ti-Nb-Sn alloy through different cooling rates. Initially, samples of Ti-Nb-Sn system were prepared through arc melting furnace. After, they were subjected to continuous cooling experiments to evaluate conditions for obtaining metastable phases. Microstructure analysis, differential scanning calorimetry and X-ray diffraction were performed in order to evaluate phase transformations. Depending on the cooling rate and composition, α” martensite, ω phase and β phase were obtained. Elastic modulus has been found to decrease as the amount of Sn was increased.

The Effects of Cooling Rate Upon Xdt m TiAl Weld Microstructure

1990 ◽  
Vol 194 ◽  
Author(s):  
Erica Robertson ◽  
Mary Ann Hill ◽  
Ricardo B. Schwarz
Keyword(s):  
Solid State ◽  
Cooling Rate ◽  
Volume Fraction ◽  
Mechanical Test ◽  
Test System ◽  
X Ray Diffraction ◽  
State Transformation ◽  
Solid State Transformation ◽  
X Ray ◽  
Weld Microstructure

AbstractFusion zone microstructures of an electron beam (EB) welded XDt m Ti–48at%Al + 6.5 vol% TiB2 alloy revealed plate-like precipitates which were absent in the base metal. The volume fraction of this phase increased with increasing cooling rate and correlated with increased weld cracking frequency. To determine whether this phase was a product of solidification from the melt or a product of a solid-state transformation, the microstructures of the welds were compared to those of samples cycled in a Gleeble 1500/20 Thermal-Mechanical Test System which was programmed to simulate the solid-state portion of the weld cooling rates (as predicted by a Rosenthal analysis). The microstructures were characterized by X-ray diffraction, optical and by scanning electron microscopy. The plate-like phase found in the weld microstructures was identified as TiB2 occurring upon rapid solidification of the melted weld metal.

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