Effect of TiH2 on the Microstructures and Refining Performance of Al-Ti-C Master Alloy

2007 ◽  
Vol 561-565 ◽  
pp. 329-332 ◽  
Author(s):  
Hong Yu Zhuang ◽  
Xue Min Pan
Keyword(s):  
Thermal Decomposition ◽  
Master Alloy ◽  
Thermal Reaction ◽  
Grain Refining ◽  
Temperature Synthesis ◽  
Obvious Effect ◽  
High Temperature Synthesis ◽  
Master Alloys ◽  
Refining Test ◽  
Refining Performance

Al-Ti-C master alloy with or without the TiH2 was prepared by Self-propagating High-temperature Synthesis (SHS) induced by laser. The phases, composition, microstructure morphologies of master alloy and its thermal reaction process were investigated by XRD, EPMA, DTA and SEM. The results show that adding TiH2 has obvious effect in promoting the synthesizing reaction of Al-Ti-C master alloys. Active Ti atoms and catalyzing H atoms released by TiH2 thermal decomposition cause critical reacting temperature of the SHS decreasing. The addition of TiH2 affects the morphologies and distribution of TiAl3 and TiC particles (size of TiC was smaller than 1μm in diameter), and restrains the congregating tendency of TiC particles. The refining test on aluminum indicates that master alloys with TiH2 possesses more excellent grain refining perfprmance than without, because of the composition and morphology of the master alloy is cut out for refining processing.

Preparation and Characterization of Al-1Ti-3B Master Alloys by Salt Route and Evaluation of their Grain Refining Performance on Al-7Si Alloys

2014 ◽  
Vol 790-791 ◽  
pp. 173-178 ◽  
Author(s):  
Virupaxi Auradi ◽  
Shivaputrappa Amarappa Kori
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Master Alloy ◽  
Reaction Times ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Grain Refining ◽  
Refining Efficiency ◽  
Master Alloys ◽  
Refining Performance

In the present work, ternary Al-1Ti-3B master alloys were prepared in an induction furnace via salt route which involves reaction between preheated halide salts (K2TiF6 and KBF4) and liquid molten Al. During preparation process parameters such as reaction temperatures of 800, 900, 1000°C and reaction times 45, 60, 75 min. have been used to study the influence of these parameters on the morphology of particles present in the master alloy and inturn on the grain refining efficiency of Al-7Si alloy. The indigenously prepared master alloys were characterized by chemical analysis; particles size analysis, XRD and SEM/EDX microanalysis. Results of particle size analysis suggest that the sizes of the particles present in Al-1Ti-3B master alloys increases with increase in reaction temperature (800-1000°C) and reaction time (45-75 min.). However, the population of the particles having sizes less than 10µm decreases with increase in reaction time and temperature. Further, SEM/EDX studies revealed different morphologies of the particles present in the master alloy when processed at different reaction temperatures and reaction times. Further, the performances of the above-prepared master alloys were assessed for their grain refining efficiency on Al-7Si alloy by DAS analysis and by CACCA studies. Results of grain refinement studies and CACCA studies suggest that, Al-1Ti-3B master alloy prepared at reaction temperature of 800°C with a reaction time of 60min. shows better grain refining performance on Al-7Si alloy when compared to the same master alloy prepared under different processing conditions.

Effects of Ti Powder Additions in Melt-SHS Process on the Performance of Al-Ti-B Grain Refiner Alloys

2016 ◽  
Vol 877 ◽  
pp. 121-126
Author(s):  
He Li ◽  
Li Hua Chai ◽  
Zhi Lei Xiang ◽  
Yong Shuang Cui ◽  
Zi Yong Chen
Keyword(s):  
Master Alloy ◽  
Reaction Rate ◽  
Grain Refining ◽  
Grain Refiner ◽  
Temperature Synthesis ◽  
Refining Efficiency ◽  
Strip Shape ◽  
High Temperature Synthesis ◽  
Al Powder ◽  
Ti Powder

Melt-SHS (Self-propagating High-temperature Synthesis) was used for the preparation of Al–5Ti–1B master alloy. The quality ratio of Ti powder/TiO2 in initial powder mixture was varied from 0:1 to 1:0. The AES, XRD and SEM were applied to evaluate the microstructure and phase componet. The results showed that the Al-5Ti-1B master alloy could be successful produced by the reaction of Al powder, TiO2 and H3BO3 in Al melt, while the reaction rate was slow. The microstructure mainly presents the TiAl3 particles with long strip shape. A significant improvement was noted both in reaction rate and in the grain refining efficiency when Ti powder was added to the reactants and the optimized ratio of Ti powder/TiO2 was 2:3. The TiAl3 particles were reduced and the grain refining efficiency turned bad when Ti powder was totally used to supply Ti

Effect of C/Ti Ratio and Al Powder Size on Microstructure and Performance of Al-Ti-C Grain Refiner

2007 ◽  
Vol 353-358 ◽  
pp. 2981-2984
Author(s):  
Chun Xiang Xu ◽  
Li Ping Liang ◽  
Bin Feng Lu ◽  
Jin Shan Zhang ◽  
Wei Liang
Keyword(s):  
Powder Size ◽  
Grain Refining ◽  
Grain Refiner ◽  
Casting Method ◽  
High Temperature Synthesis ◽  
Method Effects ◽  
Refining Performance ◽  
Al Powder ◽  
And Performance ◽  
Microstructure And Performance

Al-Ti-C grain refiners have been prepared by combining self-propagating high-temperature synthesis (SHS) technique and melting-casting method. Effects of Al powder size and C/Ti ratio on the microstructures and grain-refining efficiency of Al-Ti-C grain refiners were studied by OM, XRD, SEM and EDS. The results show that when Al powder size is fine, and C/Ti ratio is 1: 8, SHS reaction among the mixed powders can easily carry on in the melt. As a result, the prepared grain refiner consists of blocky Al3Ti and fine TiC particles distributed in Al matrix, and exhibits excellent grain refining performance on commercially pure Al.

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.

Research on Microstructure and Refining Effect of Al-3Ti-0.5B Master Alloy Produced with Ti Sponge

2011 ◽  
Vol 66-68 ◽  
pp. 845-849
Author(s):  
Xiao Wei Chen ◽  
Ya Gao ◽  
Hong Liang Zhao ◽  
Kang Rong Weng ◽  
Bao Feng Zhang
Keyword(s):  
Grain Size ◽  
Master Alloy ◽  
Molten Aluminum ◽  
Grain Refining ◽  
Commercial Purity ◽  
Average Grain Size ◽  
Feeding Methods ◽  
Refining Performance ◽  
Second Phases ◽  
Commercial Purity Aluminum

Al-3Ti-0.5B master alloy was prepared by reaction of Ti sponge, KBF4with aluminum melt. The morphology and distribution of the second phases effected by the feeding methods have been discussed. And the grain refining performance and the resistance to fading of the master alloy were investigated. The result shows that the Al-3Ti-0.5B master alloy which was prepared by adding mixture of Ti sponge and KBF4power into molten aluminum contains a large number of granular TiB2phase and blocky TiAl3phase. The average grain size of commercial purity aluminum was refined from 920μm to 120μm by adding 0.5wt.% of the master alloy. And the refining performance of the master alloy shows no obviously fading phenomenon when the holding time up to 30min.

Influence of microstructure on grain refining performance of Al–Ti–B master alloys

1993 ◽  
Vol 9 (2) ◽  
pp. 97-103 ◽  
Author(s):  
C. D. Mayes ◽  
D. G. McCartney ◽  
G. J. Tatlock
Keyword(s):  
Grain Refining ◽  
Master Alloys ◽  
Refining Performance

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.

Microstructure and Grain Refining Performance of a Rapidly Solidified Al-5Ti-1B Master Alloy

2007 ◽  
Vol 546-549 ◽  
pp. 755-760
Author(s):  
Yan Feng Han ◽  
Da Shu ◽  
Lan Jin ◽  
Jun Wang ◽  
Bao De Sun
Keyword(s):  
Master Alloy ◽  
Large Scale ◽  
Continuous Production ◽  
Tib2 Particle ◽  
Grain Refining ◽  
Purity Aluminium ◽  
Rotating Liquid ◽  
Spinning Process ◽  
Refining Performance ◽  
Rapidly Solidified

A rapidly solidified Al-5Ti-1B master alloy prepared by the in-rotating-liquid spinning process has been investigated. It has been found that the in-rotating-liquid spinning process is a potential rapid solidification method to realize the continuous production of the master alloy wire on a large scale. The microstructure of the Al-5Ti-1B was evidently improved after being rapidly solidified. The agglomeration of the TiB2 particle was significantly decreased. Consequently, the grain size of the purity aluminium refined by the rapidly solidified Al-5Ti-1B was reduced by 15% compared with that refined by the master alloy prepared under normal conditions.

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