Effects of cooling rate and magnetic field on solidification characteristics of Au80Sn20 eutectic solder

2017 ◽  
Vol 29 (1) ◽  
pp. 436-445 ◽  
Author(s):  
Yufeng Huang ◽  
Wensheng Liu ◽  
Yunzhu Ma ◽  
Yikai Wang ◽  
Siwei Tang
Keyword(s):  
Magnetic Field ◽  
Cooling Rate ◽  
Eutectic Solder

Influence of Temperature-Time Mode of Crystallization on Electrophysical Characteristics of the Polypropylene/Magnetite Nanocomposite

2019 ◽  
Vol 201 (1) ◽  
pp. 218-223
Author(s):  
M. A. Ramazanov ◽  
H. A. Shirinova ◽  
F. V. Hajiyeva ◽  
A. Kh. Karimova
Keyword(s):  
Magnetic Field ◽  
Dielectric Permittivity ◽  
Cooling Rate ◽  
Polymer Nanocomposites ◽  
Hot Pressing ◽  
Nanocomposite Materials ◽  
Negative Magnetoresistance ◽  
Electrophysical Properties ◽  
Influence Of Temperature ◽  
Temperature Time

In the present study, the influence of the temperature–time mode of crystallization (TTC) on the electrophysical properties of polymer-based PP + Fe3O4 nanocomposite materials was investigated. Also, the effect of the temperature-time mode of crystallization of nanocomposites on the negative magnetoresistance (NMR) effect that observed in this material was investigated. It was found that dielectric permittivity of polymer nanocomposites rises with increasing of cooling rate. The cooling rate of nanocomposites after hot-pressing also affects the NMR effect of these materials. The conductivity of the material under the influence of magnetic field improves with increasing of its cooling rate, which leads to increasing of NMR effect.

scholarly journals A Rapid Thermal Nanoimprint Apparatus through Induction Heating of Nickel Mold

Micromachines ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 334 ◽  
Author(s):  
Xinxin Fu ◽  
Qian Chen ◽  
Xinyu Chen ◽  
Liang Zhang ◽  
Aibin Yang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Cooling Rate ◽  
Induction Heating ◽  
Nanoimprint Lithography ◽  
High Speed ◽  
Eddy Currents ◽  
Magnetic Hysteresis ◽  
Alternating Magnetic Field ◽  
Polymer Materials ◽  
Heating And Cooling

Thermal nanoimprint lithography is playing a vital role in fabricating micro/nanostructures on polymer materials by the advantages of low cost, high throughput, and high resolution. However, a typical thermal nanoimprint process usually takes tens of minutes due to the relatively low heating and cooling rate in the thermal imprint cycle. In this study, we developed an induction heating apparatus for the thermal imprint with a mold made of ferromagnetic material, nickel. By applying an external high-frequency alternating magnetic field, heat was generated by the eddy currents and magnetic hysteresis losses of the ferromagnetic nickel mold at high speed. Once the external alternating magnetic field was cut off, the system would cool down fast owe to the small thermal capacity of the nickel mold; thus, providing a high heating and cooling rate for the thermal nanoimprint process. In this paper, nanostructures were successfully replicated onto polymer sheets with the scale of 4-inch diameter within 5 min.

Hydrodynamics and Warmth Trade in Cycles of Cooling of an Attractive Plate in an Attractive Fluid in the Attractive Field

2021 ◽  
Vol 19 (11) ◽  
pp. 32-39
Author(s):  
S.A.A. Alsaati ◽  
Qasim Shakir Kadhim ◽  
Maher Hassan Rashid ◽  
Tuqa Mohammed Jawad Abd UlKadhim
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Heat Exchange ◽  
Cooling Rate ◽  
Steel Plate ◽  
Lower Intensity ◽  
Transfer Processes ◽  
Magnetic Forces ◽  
Air Cavities ◽  
The Magnetic Field

The effect of the magnetic field on heat transfer processes of a magnetized steel plate cooled in a magnetic fluid is experimentally studied. Thermocouples were installed at six points on the surface of the plate along its length. The plots of temperature versus time are obtained in the absence of a magnetic field and in magnetic fields of different intensity. It is found that the intensity of heat exchange depends to a large extent on the magnitude of the magnetic field and on the location of points on the surface of the plate. In a magnetic field, cooling of the central part of the plate occurs with the same intensity as in the absence of a magnetic field and with a lower intensity in comparison with other points on the surface of the plate. Near the plate ends, the cooling rate of the surface is much greater in the magnetic field than in the absence of it. With increasing magnetic field strength, the cooling rate of points in the central part of the plate decreases and is less than in the absence of a magnetic field. The dependence of heat transfer on the magnitude of the magnetic field is explained by the distribution of the magnetic forces acting on the liquid surrounding the plate and the nature of the vapor-air cavities formed near its surface. Experiments on simulation of formation and the shape of vapor-air cavities in a liquid surrounding a magnetizing plate are described.

Grain refinement effect of a pulsed magnetic field on as-cast superalloy K417

2009 ◽  
Vol 24 (8) ◽  
pp. 2670-2676 ◽  
Author(s):  
Xiaoping Ma ◽  
Yingju Li ◽  
Yuansheng Yang
Keyword(s):  
Magnetic Field ◽  
Cooling Rate ◽  
Grain Refinement ◽  
Mold Wall ◽  
Thermal Control ◽  
Pulsed Magnetic Field ◽  
Refinement Process ◽  
Melt Convection ◽  
Melt Cooling ◽  
Refinement Effect

The grain refinement effect of a pulsed magnetic field on superalloy K417 was studied. The experimental results show that fine equiaxed grains are acquired with proper thermal control under the pulsed magnetic field. The refinement effect of the pulsed magnetic field is affected by the melt cooling rate and the melt superheating. The refinement effect of the pulsed magnetic field is attributed to the dissociation of nuclei from the mold wall by melt vibration and the subsequent dispersion of nuclei by melt convection. The Joule heat and the melt convection caused by the pulsed magnetic field may defer the formation of solidified shell, which prolongs the continuous refinement process. The decrease of melt cooling rate reduces the number of nuclei produced on the mold wall but prolongs the duration for the nuclei to depart from the mold wall and disperse in the melt, which enhances the refinement effect of the pulsed magnetic field. The increase of melt superheating lessens the survival probability of the nuclei in the melt, which weakens the refinement effect of the pulsed magnetic field.

Grain Refinement and Nuclei Formation Mechanism of Ni-Based Superalloy K417 with Low Voltage Pulsed Magnetic Casting

2010 ◽  
Vol 654-656 ◽  
pp. 428-431
Author(s):  
Yuan Sheng Yang ◽  
Xiao Ping Ma ◽  
Ying Ju Li
Keyword(s):  
Magnetic Field ◽  
Cooling Rate ◽  
Grain Refinement ◽  
Formation Mechanism ◽  
Low Voltage ◽  
Experimental Results ◽  
Pulsed Magnetic Field ◽  
Melt Flow ◽  
Refinement Mechanism ◽  
Refinement Effect

Low Voltage Pulsed Magnetic Casting (LVPMC) is developed for grain refinement castings in recent years. This paper investigates the grain refinement effect of LVPMC on superalloy K417 and deals with the effects of cooling rate and superheating on grain refinement, as well as grain refinement mechanism. The experimental results show that the grains in the alloy are equiaxed and refined to 60 m averagely. The melt flow and Joule heat during solidification are modeled and simulated to reveals the grain refinement mechanism. It is considered that the melt vibration and convection caused by the pulsed magnetic field, as well as cooling rate and superheating contribute to the refinement of solidified grains.

Proton NMR Investigations of the Smectic-C Phases of Three Alkyloxy-Azoxybenzenes

1983 ◽  
Vol 38 (4) ◽  
pp. 434-446 ◽  
Author(s):  
St. Limmer ◽  
M. Findeisen
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Cooling Rate ◽  
Strong Magnetic Field ◽  
Proton Nmr ◽  
The Other ◽  
Magnetic Field Direction ◽  
Slow Cooling ◽  
Smectic C ◽  
Second Moments

Proton NMR investigations of the smectic-C phases of three 4,4′-bis-n-alkyloxy-azoxybenzenes (C7, C8 , C9) with temperature independent tilt angles are presented.The behaviour of well-aligned samples (strong magnetic field ≳ 1.5 T, slow cooling rate) under rotation in the field can be described by the models of Luz and Meiboom, and Wise, Smith, and Doane, (LM/WSD), resp. However, on polarization of the samples in presence of magnetic fields ≲ 0.75 T the molecular directors are not arranged preferentially parallel to the direction of the polarizing magnetic field but are rather inclined, i.e., the layers are stacked preferentially perpendicular to the original magnetic field direction (PSL model). It is shown that all the angular dependences of NMR second moments can be interpreted in terms of a superposition of the LM/WSD and PSL models, or, on the other hand, by assuming totally disordered fractions of the samples together with portions that fully obey the behaviour demanded by one of the above models (LM/WSD or PSL). The tilt angles derived from the comparison of experimental and theoretical angular dependences of the second moments for well-aligned samples are applied to the explanation of the experiments at lower polarizing fields successfully, too.

Morphology and Distribution of in Al-Fe Alloy under an Alternating Magnetic Field

2007 ◽  
Vol 546-549 ◽  
pp. 933-936
Author(s):  
Yi Han ◽  
Chun Yan Ban ◽  
Shi Jie Guo ◽  
Qi Xian Ba ◽  
Jian Zhong Cui
Keyword(s):  
Magnetic Field ◽  
Cooling Rate ◽  
Lorentz Force ◽  
Low Frequency ◽  
Alternating Magnetic Field ◽  
Al Matrix

The aim of this work is to study the effect of a low frequency alternating magnetic field on morphology and distribution of A3F2 in the Al-2.89 wt.% Fe alloy. At the cooling rate of 0.05 °C/s, only Al3Fe phase was observed in the iron-containing intermetallics. It was noteworthy that, compared with the conventional solidification, the primary Al3Fe phase was refined and accumulated towards the center of the sample by applying the alternating magnetic field. This phenomenon is considered as the result of the larger Lorentz force acting on the Al3Fe phase than the Al matrix.

Sign in / Sign up

Export Citation Format

Share Document