Effect of Electromagnetic Stirring on Tin Bronze Plate Blank

2009 ◽  
Vol 610-613 ◽  
pp. 202-205
Author(s):  
Hua Qing Li ◽  
Chao Jian Xiang ◽  
Zhong Ping Chen ◽  
Ming Pu Wang
Keyword(s):  
Grain Size ◽  
Electromagnetic Field ◽  
Flow Behavior ◽  
Simulated Data ◽  
Electromagnetic Stirring ◽  
Continuous Cast ◽  
Inverse Segregation ◽  
Tin Bronze ◽  
Factory Test ◽  
Test Parameters

In the present work, the effect of electromagnetic field on the microstructure and the alloying agent distribution was investigated. Tin element was shown to have the tendency to be inversely segregated on the surface of tin bronze. The microstructures of the continuous cast tin bronze plates are coarse and inhomogeneous. The factory test parameters were determined according the simulated data. The flow behavior of the mercury to be stirred as well as the relations between the microstructure of plate blanks and the current parameters were analyzed. With an appropriate electromagnetic stirring, the inverse segregation of tin for C51900 alloy plant blank was improved by 80%, and the microstructure was refined from about 10mm to 1~3mm in grain size.

The Influence of the Electromagnetic Field Power on the Solidification of the Casting

2013 ◽  
Vol 395-396 ◽  
pp. 318-322
Author(s):  
Ji Guang Li ◽  
An Hong Li ◽  
Chang Jun Xu ◽  
Xing Xing Sheng ◽  
Xing Long Sun ◽  
...  
Keyword(s):  
Grain Size ◽  
Electromagnetic Field ◽  
Crystal Morphology ◽  
Electromagnetic Stirring ◽  
Ingot Casting ◽  
Columnar Crystal ◽  
Electromagnetic Power ◽  
Conventional Production ◽  
Internal Crystal ◽  
Field Production

The electromagnetic stirring technique was used in the experiment to prepare the ingot casting. After comparing the conventional production by the means of ingot casting through electromagnetic field production, the results showed that the solidification of crystal was significantly influenced by the electromagnetic power. As the powers of the agitator increasesed from 0 KW to 20 KW, the refined grain size could be easily detected. That means, the length of the columnar crystal had shortened and isometric crystal had increased dramatically. From the phase transformation we can see that the pearlite and ferrite were distributed much more uniform than the original specimens. The results of the test showed that strengthening electromagnetic field is one of the most important methods to modify the internal crystal morphology. In conclusion, the electromagnetic stirring played a key role in ingot casting.

Influence of Electromagnetic Field on the Solidification Structure of C90500 Tin Bronze

2010 ◽  
Vol 156-157 ◽  
pp. 1670-1674 ◽  
Author(s):  
Bao Mian Li ◽  
Hai Tao Zhang ◽  
Jian Zhong Cui
Keyword(s):  
Electromagnetic Field ◽  
Solidification Structure ◽  
Current Intensity ◽  
Inverse Segregation ◽  
Tin Bronze ◽  
Δ Phase ◽  
Columnar To Equiaxed Transition

The effect of electromagnetic field on the solidification structure of C90500 tin bronze (Cu-10%Sn-2%Zn in mass%) had been investigated in this paper. The results show that applying electromagnetic field during the solidification of C90500 tin bronze can refine macrostructure and δ phase, promote columnar-to-equiaxed transition, inhibit inverse segregation of Sn, and make the dendrite degenerate. The width of eutectoid structure (α-Cu+δ) becomes smaller, and the morphology of eutectoid δ changes from coarse acicular and massive shape to fine dotlike shape. The above mentioned effects become more obvious with the increasing of current intensity.

Effects of Intensity of Alternating Electromagnetic Field on Microstructure and Property of ZL114A Aluminum Alloy Castings

2013 ◽  
Vol 278-280 ◽  
pp. 429-432
Author(s):  
Qing Song Yan ◽  
Yong Li ◽  
Gang Lu ◽  
Bai Ping Lu ◽  
Bo Wen Xiong ◽  
...  
Keyword(s):  
Grain Size ◽  
Electromagnetic Field ◽  
Aluminum Alloy ◽  
Mechanical Performance ◽  
Great Influence ◽  
Current Intensity ◽  
Alloy Castings

Through analyzing and testing the microstructure and property of ZL114A aluminum alloy castings under the condition of alternating electromagnetic field, the effects of the intensity of alternating electromagnetic field on the microstructure and property of ZL114A aluminum alloy castings are studied. The results showed the intensity of alternating electromagnetic field had a great influence on the microstructure and property of ZL114A aluminum alloy castings. With the increase of the intensity of alternating electromagnetic field, the grain size of ZL114A aluminum alloy was more and more small, under the 10A current intensity, the grain was the finest. Whereas, with the increase of the intensity of alternating electromagnetic field further, the grain is more and more big. Meanwhile, in a certain rang of current intensity, the mechanical performance of ZL114A aluminum alloy had been improved comprehensively, its tensile intensity was improved 10MPa and the elongation was increased by 30%.

Microstructure and Macrosegregation of Ф508 mm 7050 Aluminum Alloy Billet under Internal Electromagnetic Stirring

2020 ◽  
Vol 993 ◽  
pp. 130-137
Author(s):  
Yang Qiu ◽  
Zhi Feng Zhang ◽  
Hao Dong Zhao ◽  
Yong Tao Xu
Keyword(s):  
Grain Size ◽  
Aluminum Alloy ◽  
Electromagnetic Stirring ◽  
Alloying Elements ◽  
Homogeneous Distribution ◽  
Second Phase ◽  
7050 Aluminum Alloy ◽  
Fine Microstructure

To obtain fine microstructure and homogeneous distribution of alloying elements in the large-sized billet, the internal electromagnetic stirring as a new electromagnetic stirring method was proposed and utilized for the preparation of Ф508 mm 7050 aluminum alloy billet. The results demonstrate that the internal electromagnetic stirring could refine the microstructure and second phase, and alleviated the macrosegregation significantly. The grain size at the edge, 1/2 radius, and center of the billet decreased to 180 μm, 175 μm, and 185 μm, respectively. Moreover, the relative macrosegregation of Zn, Mg, and Cu at the edge and center decreased to 3.9% and 2.8%, 2.3% and 1.6%, 4.1% and 2.5%, respectively.

scholarly journals Nonlinear Flow Behavior in Packed Beds of Natural and Variably Graded Granular Materials

2019 ◽  
Vol 131 (3) ◽  
pp. 957-983 ◽  
Author(s):  
J. H. van Lopik ◽  
L. Zazai ◽  
N. Hartog ◽  
R. J. Schotting
Keyword(s):  
Grain Size ◽  
Granular Materials ◽  
Flow Behavior ◽  
Nonlinear Flow ◽  
Packed Beds ◽  
Size Distributions ◽  
Flow Conditions ◽  
Grain Size Distributions ◽  
Sand And Gravel ◽  
Nonlinear Flow Behavior

AbstractUnder certain flow conditions, fluid flow through porous media starts to deviate from the linear relationship between flow rate and hydraulic gradient. At such flow conditions, Darcy’s law for laminar flow can no longer be assumed and nonlinear relationships are required to predict flow in the Forchheimer regime. To date, most of the nonlinear flow behavior data is obtained from flow experiments on packed beds of uniformly graded granular materials (Cu = d60/d10 < 2) with various average grain sizes, ranging from sands to cobbles. However, natural deposits of sand and gravel in the subsurface could have a wide variety of grain size distributions. Therefore, in the present study we investigated the impact of variable grain size distributions on the extent of nonlinear flow behavior through 18 different packed beds of natural sand and gravel deposits, as well as composite filter sand and gravel mixtures within the investigated range of uniformity (2.0 < Cu < 17.35) and porosity values (0.23 < n < 0.36). Increased flow resistance is observed for the sand and gravel with high Cu values and low porosity values. The present study shows that for granular material with wider grain size distributions (Cu > 2), the d10 instead of the average grain size (d50) as characteristic pore length should be used. Ergun constants A and B with values of 63.1 and 1.72, respectively, resulted in a reasonable prediction of the Forchheimer coefficients for the investigated granular materials.

scholarly journals The δ Phase Precipitation of an Inconel 718 Superalloy Fabricated by Electromagnetic Stirring Assisted Laser Solid Forming

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2604 ◽  
Author(s):  
Lyu ◽  
Liu ◽  
Hu ◽  
Yang ◽  
Huang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Electromagnetic Field ◽  
Field Intensity ◽  
Inconel 718 ◽  
Phase Changes ◽  
Electromagnetic Stirring ◽  
The Core ◽  
Laser Solid Forming ◽  
Δ Phase ◽  
Inconel 718 Superalloy

Fabricating an Inconel 718 superalloy using electromagnetic stirring assisted laser solid forming (EMS-LSF) is a novel method to modify its microstructure and mechanical properties by consuming the Nb element in the γ phase to alleviate interdendritic segregation. The precipitate of the δ phase at 950 °C after EMS-LSF can help to achieve the uniform diffusion of Nb, and can also improve its mechanical properties. The precipitation behavior of the δ phase in an EMS-LSF Inconel 718 superalloy with different heat treatment processes has been investigated. The results show that the morphology of the δ phase changes from rod-like to a long-needle shape and tends to grow from the inter dendrite to the core dendrite with electromagnetic field intensity increasing, which is accompanied by the “cutting” and “dissolution” of the Laves phase. Through precipitation kinetics analysis, the precipitation rate of the δ phase is seen to increase with the electromagnetic field intensity increasing. Under a combination of electromagnetic stirring and laser solid forming, the microhardness of the Inconel 718 samples increased slightly due to the fact that a higher content of Nb was distributed in the core dendrite resulting from the serious convection of liquid metal, which can strengthen the matrix.

Refinement Effect and Mechanism of AZ31 Magnesium Alloy by Electromagnetic Stirring under the Effect of Grain-Refiner

2013 ◽  
Vol 631-632 ◽  
pp. 556-561 ◽  
Author(s):  
Sheng Yuan Gao ◽  
Shi Lian Qu ◽  
Yue Yuan ◽  
Bao Qin Fu
Keyword(s):  
Grain Size ◽  
Magnesium Alloy ◽  
Heterogeneous Nucleation ◽  
Holding Time ◽  
Electromagnetic Stirring ◽  
Az31 Magnesium Alloy ◽  
Grain Refiner ◽  
Nucleation Sites ◽  
Continuously Cast ◽  
Refinement Effect

The effects of electromagnetic stirring and Al4C3grain refiner on the grain refinement of semi-continuously cast AZ31 magnesium alloy were discussed in this investigation. The results indicate that electromagnetic stirring has effective refining effect on the grain size of AZ31 magnesium alloy under the effect of Al4C3grain refiner. Electromagnetic stirring can “activate” the Al4C3particles, resulting in more heterogeneous nucleation sites for the primary α-Mg grains. But, longer holding time can “inactivate” the Al4C3particles, and the optimal experimental holding time is 60 min in the present investigation. The activated rate of the electromagnetic under the experimental condition ρ2=1.65%.

Multiple paleoecological controls on the composition of marine fossil assemblages from the Frasnian (Late Devonian) of Virginia, with a comparison of ordination methods

Paleobiology ◽  
2010 ◽  
Vol 36 (4) ◽  
pp. 573-591 ◽  
Author(s):  
Andrew M. Bush ◽  
Roderic I. Brame
Keyword(s):  
Grain Size ◽  
Species Composition ◽  
Simulated Data ◽  
Ecological Factors ◽  
Detrended Correspondence Analysis ◽  
Late Devonian ◽  
Opportunistic Species ◽  
Disturbance Intensity ◽  
Fossil Assemblages ◽  
Highly Correlated

Ecological ordination can reveal gradients in the species composition of fossil assemblages that can be correlated with paleoenvironmental gradients. Ordinations of simulated data sets suggest that nonmetric multidimensional scaling (NMDS) generally produces less distorted results than detrended correspondence analysis (DCA). We ordinated 113 brachiopod-dominated samples from the Frasnian (Late Devonian) Brallier, Scherr, and lower Foreknobs Formations of southwest Virginia, which represent a range of siliciclastic marine paleoenvironments. A clear environmental signal in the ordination results was obscured by (apparently) opportunistic species that occurred at high abundance in multiple environments; samples dominated by these species aggregated in ordination space regardless of paleoenvironmental provenance. After the opportunist-dominated samples were removed, NMDS revealed a gradient in species composition that was highly correlated with substrate (grain size); a second, orthogonal gradient likely reflects variation in disturbance intensity or frequency within grain-size regimes. Additional environmental or ecological factors, such as oxygenation, may also be related to the gradients. These two gradients, plus the environmental factors that controlled the occurrence of opportunistic species, explain much of the variation in assemblage composition in the fauna. In general, the composition of fossil assemblages is probably influenced by multiple paleoecological and paleoenvironmental factors, but many of these can be decomposed and analyzed.

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