An Investigation on Grain Refinement Mechanism of Master Alloys Al-Ti, Al-TiC and Al-Ti-C Toward Pure Aluminum

2013 ◽  
Vol 652-654 ◽  
pp. 1072-1075 ◽  
Author(s):  
Wan Wu Ding ◽  
Jiang Tao Zhu ◽  
Wen Jun Zhao ◽  
Tian Dong Xia
Keyword(s):  
Grain Refinement ◽  
Heterogeneous Nucleation ◽  
Pure Aluminum ◽  
Grain Refining ◽  
Nucleation Effect ◽  
Commercially Pure ◽  
Master Alloys ◽  
Refinement Mechanism ◽  
Heat Preservation

The grain refining effects of Al-Ti, Al-TiC and Al-Ti-C master alloys on commercially pure aluminum were compared, and the grain refinement mechanism of TiAl3 and TiC among master alloys was discussed. The results show that: the grain refinement of the master alloys Al-TiC and Al-Ti toward pure aluminum mainly stems from the heterogeneous nucleation role of TiC and TiAl3 particles, but with the extension of heat preservation time of fused mass, its role of heterogeneous nucleation will decline due to dissolution of TiAl3 and aggregation and precipitation of TiC. The preferable grain refinement effects of Al-Ti-C master alloys toward pure aluminum are mainly due to the fact that when TiAl3 and TiC particles are acted commonly as heterogeneous nucleation particles, the heterogeneous nucleation effect of TiC particles will be enhanced because of the presence of TiAl3.

The Behavior of AlTiC Master Alloys in Grain Refining of Commercial and High Pure Aluminum

2005 ◽  
Vol 475-479 ◽  
pp. 313-316
Author(s):  
Jian Guo Li ◽  
Min Huang ◽  
Zimu Shi ◽  
Dong Yu Liu
Keyword(s):  
Master Alloy ◽  
Heterogeneous Nucleation ◽  
Pure Aluminum ◽  
Grain Refining ◽  
Refining Efficiency ◽  
Master Alloys

The AlTiC master alloy has been prepared in different components to refine 99.8%Al and 99.98％Al, then compared to two typical Al5Ti1B in refining efficiency and the grain nuclear. The result showed that the refining efficiency seemed better if the nucleation of high pure aluminum revealed complexity and variety. It may due to that the latency heterogeneous nucleation was efficient on the whole, consequently accelerated refining efficiency.

Effect of Temperature on the Performance of AlTiC Metal Alloys

2011 ◽  
Vol 339 ◽  
pp. 291-294
Author(s):  
Yong Feng Wang ◽  
Rui Li
Keyword(s):  
Pure Aluminum ◽  
Metal Alloys ◽  
Effect Of Temperature ◽  
Grain Refining ◽  
X Ray Diffraction ◽  
X Ray ◽  
Commercially Pure ◽  
Master Alloys ◽  
Refining Performance ◽  
Al3ti Particle

AlTiC master alloys have been prepared by Contact Reaction Method（CRM）.X-ray diffraction，SEM and EDS were used to analyse the AlTiC master alloys. It showed that morphology and distribution of TiC and Al3Ti particle have correspondingly changed with the transformation of temperature. As a result, the change in morphology and distribution of TiC and Al3Ti particle has considerably affected the gain refining performance of AlTiC master alloys. The result showed that it had excellent grain refining performance for commercially pure aluminum in 800°C.

Grain Refinement Mechanism and Effective Nucleation Phase of Al-5Ti-1B Master Alloy

2017 ◽  
Vol 898 ◽  
pp. 1231-1235 ◽  
Author(s):  
Shun Cheng Wang ◽  
Ji Lin Li ◽  
Chun Lei Gan ◽  
Kai Hong Zheng
Keyword(s):  
Grain Size ◽  
Grain Refinement ◽  
Master Alloy ◽  
Pure Aluminum ◽  
Grain Refiner ◽  
Crystal Nucleus ◽  
Master Alloys ◽  
Refinement Mechanism ◽  
Nucleation Phase ◽  
Heterogeneous Nucleus

The Al-5Ti-1B, Al-10Ti, Al-4B master alloys and TiB2 powder were applied to refine the pure aluminum, respectively. The effects of the TiAl3 phase, TiB2 particle, and AlB2 phase on the grain size of pure aluminum were compared. The grain refinement mechanism of the Al-5Ti-1B grain refiner was studied. The results showed that the TiAl3 phase was an effective heterogeneous nucleus of the α-Al grain. But the TiAl3 phase in the Al-5Ti-1B grain refiner was not the heterogeneous nucleus of the α-Al grain due to its re-melting in the Al melt. The separate TiB2 particle or AlB2 phase was not the heterogeneous nucleus of the α-Al grain. However, the TiB2 coated by the TiAl3 phase can be the effective heterogeneous nucleus of the α-Al grain. The grain refinement mechanism of the Al-5Ti-1B grain refiner can be summarized as follows: when the Al-5Ti-1B grain refiner is added into the Al melt, the TiAl3 phases are re-melted to release the Ti atoms, while the TiB2 particles are remaining in the Al melt. During the solidification of the Al melt, the Ti atoms are segregating on the surface of TiB2 particles to form the TiAl3 phases. The TiB2 particles coated by the TiAl3 phases then reacts with the Al melt to generate α-Al crystal nucleus.

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.

scholarly journals Grain refinement of commercially pure aluminum with addition of Ti and Zr elements based on crystallography orientation

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Zhongwei Chen ◽  
Kang Yan
Keyword(s):  
Grain Refinement ◽  
Heterogeneous Nucleation ◽  
Pure Aluminum ◽  
Al Alloys ◽  
Orientation Relationships ◽  
Grain Refiner ◽  
Heterogeneous Nucleation Site ◽  
Edge Matching ◽  
Commercially Pure ◽  
Al Matrix

Abstract The edge-to-edge matching (E2EM) model and electron back-scatter diffraction (EBSD) technique are used to explore the grain refinement mechanism of commercially pure Al through the addition of Ti and Zr elements. EBSD results show that there are favorable crystallography orientation relationships (ORs) between both Al3Ti and Al3Zr particles with α-Al matrix. Due to these ORs Al3Ti and Al3Zr particles act as the heterogeneous nucleation site during solidification nucleation of Al–Ti and Al–Zr alloys, respectively. Furthermore, both Al3Ti and Al3Zr particles have small values of interplanar spacing mismatch and interatomic spacing misfit with respect to α-Al matrix by using E2EM. It shows that micro-addition of Ti and Zr element is efficient heterogeneous nucleation refiner in commercial purity Al or Al alloys. Besides, there may be some other mechanisms in grain refinement of Al alloys with addition of Ti grain refiner.

Effect of Zr Addition on the Mechanical Behavior, Ductility and Wear Resistance of Aluminum Grain Refined by Titanium

2010 ◽  
Vol 442 ◽  
pp. 15-25 ◽  
Author(s):  
A.I.O. Zaid ◽  
S.M.A. Al-Qawabah
Keyword(s):  
Mechanical Properties ◽  
Phase Diagram ◽  
Wear Resistance ◽  
Mechanical Behavior ◽  
Grain Refinement ◽  
Pure Aluminum ◽  
Columnar Structure ◽  
Grain Refining ◽  
Commercially Pure ◽  
Zr Addition

Aluminum and its alloys are the second most commonly used metal for a variety of engineering applications. They solidify in columnar structure with large grain size which normally affects their mechanical behavior and surface quality. It is now becoming customary in aluminum foundry to grain refine their structure by adding either titanium or titanium + boron to their melt before solidification. In this paper, the effect of addition of Ti on the mechanical properties, ductility and wear resistance of commercially pure aluminum is investigated. Titanium was added at a level of 0.15 % wt. This ratio corresponds to the peritictic limit on the Al-Ti phase diagram and is normally used for grain refining of aluminum. It was found that addition of Ti at this level resulted in grain refinement of aluminum structure whereas addition of Zr alone resulted in grain coarsening of Al structure while it resulted in grain refinement when it is added in the presence of Ti. Regarding the effect of Zr on the wear resistance of aluminum it was found that at small loads and speeds addition of Ti or Zr or both together resulted in deterioration of its wear resistance whereas at higher loads and speeds resulted in pronounced improvement of its wear resistance.

Grain refinement mechanism of pure aluminum by inoculation with Al–B master alloys

2012 ◽  
Vol 549 ◽  
pp. 136-143 ◽  
Author(s):  
Tongmin Wang ◽  
Zongning Chen ◽  
Hongwang Fu ◽  
Lei Gao ◽  
Tingju Li
Keyword(s):  
Grain Refinement ◽  
Pure Aluminum ◽  
Master Alloys ◽  
Refinement Mechanism

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”.

Influence of Reaction Temperature for the Manufacturing of Al-3Ti and Al-3B Master Alloys and their Grain Refining Efficiency on a Al-7Si Alloy

2007 ◽  
Vol 29-30 ◽  
pp. 111-115 ◽  
Author(s):  
S.A. Kori ◽  
V. Auradi
Keyword(s):  
Size Distribution ◽  
Grain Refinement ◽  
Reaction Temperature ◽  
Master Alloy ◽  
Induction Furnace ◽  
Grain Refining ◽  
Refining Efficiency ◽  
Master Alloys ◽  
Halide Salts ◽  
Titanium Fluoride

In the present work binary Al-3Ti and Al-3B master alloys were prepared at different reaction temperatures in an induction furnace by the reaction of halide salts like potassium fluoborate and potassium titanium fluoride with liquid molten Al. The indigenously developed master alloys were used for grain refinement studies of Al-7Si alloy and evaluated for their grain refining ability by CACCA studies. The present results suggest that, the reaction temperature influences the size, size distribution and morphology of the intermetallic (Al3Ti in Al-3Ti, and AlB2/AlB12 in Al-3B) particles present in Al-3Ti and Al-3B master alloys. Grain refinement studies of Al-7Si alloy reveal that, Al-3Ti and Al-3B master alloys prepared at 8000C-60 min. have shown better grain refining efficiency on Al- 7Si alloy when compared to the master alloys prepared at 9000C-60 min and 10000C-60 min respectively. In addition, B-rich Al-3B master alloy shows efficient grain refinement than Ti rich Al- 3Ti master alloy.

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