Effect of Electromagnetic Stirring on Morphology Evolution of Mg2Si in Hypereutectic Al-Si Alloy Composite

Mg2Si reinforced hypereutectic Al-Si composite was prepared and the effects of electro- magnetic stirring on Mg2Si particle in the composite were researched. The results indicated that there were the important effects of electromagnetic stirring on size and morphology of the particle in the composite. The morphology and size of the particle in the composite were obviously improved by electromagnetic stirring. In comparison with the sample without isothermal holding, the size of the particle isothermally held slightly increased under the same stirring condition, but the roundness of the particle was improved. After isothermal holding, the mechanical properties of the composite prepared by electromagnetic stirring were improved to some extent.

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The MSCP Process for Semi-Solid Slurry Production

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.116-117.362 ◽

2006 ◽

Vol 116-117 ◽

pp. 362-365 ◽

Cited By ~ 1

Author(s):

Zhan Feng Tian ◽

Zhi Feng Zhang ◽

Jun Xu ◽

Li Kai Shi

Keyword(s):

Continuous Production ◽

Electromagnetic Stirring ◽

Preparation Process ◽

High Quality ◽

Magnetic Stirring ◽

Continuous Preparation ◽

The Common ◽

Feedstock Production ◽

Electro Magnetic ◽

Semi Solid

Production of semi-solid slurry with fine and uniform microstructures is one of the basic and key problems for the industrial application of semi-solid processing. The common disadvantages of existing techniques are as follows: continuous production difficulty, high process controlling requirement and low quality microstructure. In order to overcome those problems, the MSCP (Multielectromagnetic Stirring Continuous Preparation) process has been developed by GRINM. Experimental results show that annular chamber for feedstock production can improve the efficiency of electromagnetic stirring and reduce the difficulty of temperature grad control. Compared with single electromagnetic stirring, multi- electro magnetic stirring can achieve more uniform stirring. Strict temperature grad control in annular chamber is the key of continuous preparation of high quality semi-solid slurry. Semi-solid slurry of different solid fractions was obtained by MSCP.

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Effects of Electro-Magnetic Stirring on Microstructural Evolution and Mechanical Properties in Semi-Solid Forming of a Hypo-Eutectic Al–Si–Cu–Ni–Mg Alloy

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.m2013404 ◽

2014 ◽

Vol 55 (4) ◽

pp. 693-699 ◽

Cited By ~ 4

Author(s):

Young-Soo Jang ◽

Byoung-Hee Choi ◽

Chun-Pyo Hong

Keyword(s):

Mechanical Properties ◽

Microstructural Evolution ◽

Mg Alloy ◽

Magnetic Stirring ◽

Electro Magnetic ◽

Semi Solid

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Development of Microstructure of Semi-Solid 6061 Alloy with Method of Alternating Electromagnetic Stirring

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.199-200.1870 ◽

2011 ◽

Vol 199-200 ◽

pp. 1870-1873

Author(s):

Wen Liu ◽

Jun Long Chen ◽

Xiao Li Ma ◽

Xu Ding

Keyword(s):

Isothermal Holding ◽

Particle Diameter ◽

Electromagnetic Stirring ◽

Isothermal Treatment ◽

Average Particle ◽

Average Particle Diameter ◽

Shape Coefficient ◽

Magnetic Stirring ◽

Semi Solid ◽

Α Particles

The semi-solid 6061 alloy was obtained with method of alternating electromagnetic stirring. The results show that compared with horizontal, vertical and spiral magnetic stirring method, alternating magnetic stirring could make eligible slurry with finer, more equiaxed and more homogeneous primary α particles in much shorter time. The microstructure evolution during isothermal treatment is studied and it is shown that the average particle diameter increases with the increase of isothermal holding time and the shape coefficient decreases somewhat at first, and then decreases sharply in the end.

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Preferential dissolution along misoriented boundaries in heterogenite

MRS Proceedings ◽

10.1557/proc-620-m5.7.1 ◽

2000 ◽

Vol 620 ◽

Author(s):

R. Lee Penn ◽

Alan T. Stone ◽

David R. Veblen

Keyword(s):

Electron Microscopy ◽

Aspect Ratio ◽

Reductive Dissolution ◽

Morphology Evolution ◽

Crystal Chemical ◽

Transmission Electron ◽

Micron Size ◽

Primary Particles ◽

Size And Morphology ◽

Preferential Dissolution

ABSTRACTHigh-Resolution Transmission Electron Microscopy (HRTEM) results show a strong crystal-chemical and defect dependence on the mode of dissolution of synthetic heterogenite (CoOOH) particles. As-synthesized heterogenite particles are micron-size plates (aspect ratio ∼ 1/30) constructed of crystallographically oriented ∼ 3-nm primary particles or are single ∼ 21-nm unattached heterogenite platelets (aspect ratio ∼1/7). Reductive dissolution, using hydroquinone, was examined in order to evaluate morphology evolution as a function of reductant concentration. Two end-member modes of dissolution were observed: 1) non-specific dissolution of macroparticles and 2) preferential dissolution along misoriented boundaries. In the case of non-specific dissolution, average macrocrystal size and morphology are not altered as building block crystals are consumed. The result is web-like particles with similar breadth and shape as undissolved particles. Preferential dissolution involves the formation of channels or holes along boundaries of angular misorientation. Such boundaries involve only a few degrees of tilt, but dissolution occurs almost exclusively at such sites. Energy-Filtered TEM thickness maps show that the thickness of surrounding material is not significantly different from that of undissolved particles. Finally, natural heterogenite from Goodsprings, Nevada, shows morphology and microstructure similar to those of this synthetic heterogenite.

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