Preparation of Semi-Solid 357.0 Slurries with Different α-Al Phase Features by Solidification from Full Liquid State and Remelting

2022 ◽  
Vol 327 ◽  
pp. 223-230
Author(s):  
Juan Chen ◽  
Xiao Gang Hu ◽  
Wen Ying Qu ◽  
Min Luo ◽  
Zhong Li ◽  
...  
Keyword(s):  
Particle Size ◽  
Power Law ◽  
Solid Fraction ◽  
Liquid State ◽  
Shape Factor ◽  
Volume Fraction ◽  
Viscosity Model ◽  
Particle Size And Morphology ◽  
Size And Morphology ◽  
Semi Solid

The characteristics of the solid phase, namely the volume fraction, particle size, and morphology, are dominant variables that can determine the viscosity of the semi-solid slurry. However, particle size and morphology were always being ignored and the solid fraction was simply determined using the temperature in the conventional power-law viscosity, resulting in a disagreement in the viscosity values in different researches. To make the power-law viscosity model more accurate for predicting the filling process of semi-solid die casting, it is essential to modify this viscosity model based on particle characteristics. Therefore, there is a fundamental demand to prepare semi-solid slurries with different α-Al phase features at first. This is achieved in this study by two kinds of heat history controlling methods: remelting and solidification, which can get slurries with spherical structure and dendric structure, respectively. The semi-solid 357.0 slurries with 0.11-0.43 solid fraction, 137-182μm particle size, and 0.81-0.90 shape factor were prepared in the remelting process, while dendritic structures (shape factor<0.5) with 0.1 and 0.3 solid fractions were obtained by solidification controlling from the full liquid state. Besides, the effect of parameters on the evolution of the α-Al phase has been discussed. These slurries with different solid features will be further used to quantify the influence of primary phase characteristics on rheological behavior and make the power-law viscosity model more accurate for simulation.

Effect of Holding Time on Microstructures of AZ91D Alloy by the Semi-Solid Thixo-Extruded Process

2015 ◽  
Vol 1088 ◽  
pp. 191-194
Author(s):  
Xiao Ping Zheng ◽  
Ze Sheng Ji ◽  
Wei Wen Zhang ◽  
Ming Shao
Keyword(s):  
Mechanical Property ◽  
Particle Size ◽  
Magnesium Alloy ◽  
Shape Factor ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Az91d Alloy ◽  
Az91d Magnesium Alloy ◽  
Semi Solid ◽  
The Relationship

The semi-solid thixo-extruded process of AZ91D magnesium alloy with 9 % plastic deformation was investigated. The effect of isothermal time on the thixo-extruded formability of AZ91D magnesium alloy was analyzed. The relationship between isothermal time and microstructure, mechanical property was also researched. The results showed that with increasing the isothermal time from zero to 60 min on 575 °C, the filling distance was increased firstly and then decreased, the solid volume fraction was decreased firstly and then increased, the tensile strength and elongation were also increased firstly and then decreased. However, the increasing isothermal time would lead to decrease of shape factor but the coarsening of particle size. When the isothermal time was 30 min, the solid volume fraction was lowest and the filling distance was greatly increased obviously.

Direct manipulation of particle size and morphology of ordered mesoporous silica by flow synthesis

RSC Advances ◽  
2015 ◽  
Vol 5 (18) ◽  
pp. 13331-13340 ◽  
Author(s):  
T. N. Ng ◽  
X. Q. Chen ◽  
K. L. Yeung
Keyword(s):  
Particle Size ◽  
Mesoporous Silica ◽  
Hollow Spheres ◽  
Ordered Mesoporous Silica ◽  
Direct Manipulation ◽  
Flow Synthesis ◽  
Precise Control ◽  
Ordered Mesoporous ◽  
Particle Size And Morphology ◽  
Size And Morphology

Flow-synthesis of mesoporous silica allows deliberate and precise control over the size and shapes and enables the preparation of complex microstructures (i.e., hollow spheres).

scholarly journals Jet Impingement Heat Transfer of Confined Single and Double Jets with Non-Newtonian Power Law Nanofluid under the Inclined Magnetic Field Effects for a Partly Curved Heated Wall

2021 ◽  
Vol 13 (9) ◽  
pp. 5086
Author(s):  
Fatih Selimefendigil ◽  
Hakan F. Oztop ◽  
Ali J. Chamkha
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Particle Size ◽  
Aspect Ratio ◽  
Power Law ◽  
Volume Fraction ◽  
Inclined Magnetic Field ◽  
Magnetic Field Effects ◽  
Power Law Nanofluid ◽  
Power Law Index

Single and double impinging jets heat transfer of non-Newtonian power law nanofluid on a partly curved surface under the inclined magnetic field effects is analyzed with finite element method. The numerical work is performed for various values of Reynolds number (Re, between 100 and 300), Hartmann number (Ha, between 0 and 10), magnetic field inclination (γ, between 0 and 90), curved wall aspect ratio (AR, between 01. and 1.2), power law index (n, between 0.8 and 1.2), nanoparticle volume fraction (ϕ, between 0 and 0.04) and particle size in nm (dp, between 20 and 80). The amount of rise in average Nusselt (Nu) number with Re number depends upon the power law index while the discrepancy between the Newtonian fluid case becomes higher with higher values of power law indices. As compared to case with n = 1, discrepancy in the average Nu number are obtained as −38% and 71.5% for cases with n = 0.8 and n = 1.2. The magnetic field strength and inclination can be used to control the size and number or vortices. As magnetic field is imposed at the higher strength, the average Nu reduces by about 26.6% and 7.5% for single and double jets with n greater than 1 while it increases by about 4.78% and 12.58% with n less than 1. The inclination of magnetic field also plays an important role on the amount of enhancement in the average Nu number for different n values. The aspect ratio of the curved wall affects the flow field slightly while the average Nu variation becomes 5%. Average Nu number increases with higher solid particle volume fraction and with smaller particle size. At the highest particle size, it is increased by about 14%. There is 7% variation in the average Nu number when cases with lowest and highest particle size are compared. Finally, convective heat transfer performance modeling with four inputs and one output is successfully obtained by using Adaptive Neuro-Fuzzy Interface System (ANFIS) which provides fast and accurate prediction results.

scholarly journals Dehumidified Air-Assisted Spray-Drying of Cloudy Beetroot Juice at Low Temperature

2021 ◽  
Vol 11 (14) ◽  
pp. 6578
Author(s):  
Aleksandra Jedlińska ◽  
Alicja Barańska ◽  
Dorota Witrowa-Rajchert ◽  
Ewa Ostrowska-Ligęza ◽  
Katarzyna Samborska
Keyword(s):  
Particle Size ◽  
Physicochemical Properties ◽  
Spray Drying ◽  
Low Temperatures ◽  
Beetroot Juice ◽  
Particle Size And Morphology ◽  
Size And Morphology ◽  
Tapped Density ◽  
Lower Loss ◽  
Better Than

This paper discusses the physicochemical properties of powders obtained by spray drying of cloudy beetroot juice, using dehumidified air in variants with or without carriers. The inlet air temperature was 130 °C or 90 °C, and the addition of the carriers was at a ratio of juice to carrier solids of 3:2. In the obtained powders, the following physicochemical properties were determined: water content and water activity, apparent density, loose and tapped density, porosity, flowability, particle size and morphology, and the content and retention of betalains. It was possible to dry cloudy beetroot juice without the use of carriers at low temperatures (90 or 130 °C). The 100% beetroot powders were characterized by satisfactory physicochemical properties, often better than those with carriers (including lower hygroscopicity and higher color saturation and yield). A lower loss of betalains was found for the powders with the addition of carriers. The best process yields were obtained for the powder without carriers at 130 °C and 90 °C.

Synthesis and Properties of (Bi0.5Na0.5)TiO3 Powders by Hydrothermal Method

2007 ◽  
Vol 336-338 ◽  
pp. 140-142
Author(s):  
Jun Jie Hao ◽  
Xiao Hui Wang ◽  
Shi Yun Lin ◽  
Long Tu Li
Keyword(s):  
Particle Size ◽  
Hydrothermal Method ◽  
Single Phase ◽  
Piezoelectric Ceramics ◽  
Treatment Temperature ◽  
Lead Free ◽  
Excellent Candidate ◽  
Traditionally Prepared ◽  
Particle Size And Morphology ◽  
Size And Morphology

Na0.5Bi0.5TiO3 (NBT) is considered to be an excellent candidate for lead-free piezoelectric ceramics. In this study, we propose a hydrothermal method for the preparation of single phase NBT powder at relatively low treatment-temperature. The particle size and morphology of the synthesized powders were examined by SEM. The powders were further pressed into disk and sintered at 1120°C/2h in air, and its properties and microstructure were compared with traditionally prepared samples.

Particle-size and morphology dependence of the preferred interface orientation in LiFePO4 nano-particles

2014 ◽  
Vol 2 (37) ◽  
pp. 15437-15447 ◽  
Author(s):  
Aziz Abdellahi ◽  
Oncu Akyildiz ◽  
Rahul Malik ◽  
Katsuyo Thornton ◽  
Gerbrand Ceder
Keyword(s):  
Particle Size ◽  
First Principles ◽  
Nano Particles ◽  
Particle Size And Morphology ◽  
Interface Orientation ◽  
Size And Morphology

Using calculations based on first principles, we demonstrate that the preferred interface in singles LiFePO4 particles depends both on the particle size and morphology.

Effect of particle size and morphology on the properties of luminescence in ZnWO4

2014 ◽  
Vol 153 ◽  
pp. 130-135 ◽  
Author(s):  
V.M. Lisitsyn ◽  
D.T. Valiev ◽  
I.A. Tupitsyna ◽  
E.F. Polisadova ◽  
V.I. Oleshko ◽  
...  
Keyword(s):  
Particle Size ◽  
Effect Of Particle Size ◽  
Particle Size And Morphology ◽  
Size And Morphology
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