Rheological Properties and Microstructure of Hypereutectic Semi-Solid Al-Si-Mg Alloys Using Rheocasting Route

2012 ◽  
Vol 192-193 ◽  
pp. 323-328 ◽  
Author(s):  
Mehand Tebib ◽  
Frank Ajersch ◽  
X. Grant Chen
Keyword(s):  
Solid State ◽  
Rheological Properties ◽  
Parallel Plate ◽  
Fluid Model ◽  
Flow Behavior ◽  
Microstructural Study ◽  
Shear Rates ◽  
Solid Phases ◽  
Semi Solid ◽  
Liquid And Solid Phases

The SEED rheocasting process was used to produce semi-solid slurries of hypereutectic Al-17Si-4.5Cu (A390) and Al-15Si-10.5Mg-4Cu alloys respectively. The rheological properties of these alloys in the semi-solid state were characterized at different deformation rates and at variable solid fractions using the parallel plate compression viscometry. The viscosity at different shear rates was calculated using a Newtonian fluid model for increments of deformation during compression. Microstructures of both alloys, after partial solidification and compression, were examined in order to characterize the flow behavior during deformation. The comparison of the viscosity between the A390 and Al-15Si-10.5Mg-4Cu alloys indicated that the high Mg containing alloy possessed a higher viscosity for the range of shear rates and solid fractions investigated. Rheological results showed that at a given solid fraction, the viscosity of both alloys decreased significantly with increasing shear rates, indicating a shear thinning behavior. In addition, a separation of liquid and solid phases was also observed for both alloys in the microstructural study of compressed semi-solid billets.

Influence of Morphology on the Rheological Behavior of Semi-Solid A356 Aluminum Alloy

2006 ◽  
Vol 116-117 ◽  
pp. 601-605
Author(s):  
Heng Hua Zhang ◽  
Xian Nian Zhang ◽  
Guang Jie Shao ◽  
Luo Ping Xu ◽  
Yi Tao Yang ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Solid State ◽  
Rheological Behavior ◽  
Apparent Viscosity ◽  
Flow Behavior ◽  
A356 Alloy ◽  
Solid Alloy ◽  
A356 Aluminum Alloy ◽  
A356 Aluminum ◽  
Semi Solid

The morphology of semi-solid alloy is one of the key influence factors on the rheological behavior of slurry during die filling and the mechanical properties of formed parts. However, it is difficult to study such effect due to hard controlling of morphology in semi-solid state. In this paper, a self-developed Searle-type viscometer was used to determine the rheological behavior of A356 aluminum alloy in different morphology, which was refined with the salts mixture of K2TiF6 and KBF4. The results indicated that the flow behavior of refined A356 alloy in the semi-solid state possesses obviously thixotropic behavior under isothermal shearing condition with less time to reach steady state and lower steady apparent viscosity as compared to that of the A356 alloy. During continuous cooling at a constant shearing rate, the apparent viscosity of refined A356 slurry in the same solid fraction decreased with the content of Ti. It is shown from quantitative image analysis that the primary α-Al grain in the refined alloy evolves from dendrites to rosettes or sphericitys, and then tends to be rounder and finer in higher Ti content. The mechanism of the influence of morphology on rheological behavior was also discussed in this paper.

scholarly journals Annular frictional pressure losses for drilling fluids

2020 ◽  
pp. 1-19
Author(s):  
Arild Saasen ◽  
Jan David Ytrehus ◽  
Bjørnar Lund
Keyword(s):  
Pressure Loss ◽  
Parallel Plate ◽  
Fluid Model ◽  
Axial Flow ◽  
Measured Data ◽  
Drilling Fluids ◽  
Laboratory Measurements ◽  
Model Approximation ◽  
Pressure Losses ◽  
Shear Rates

Abstract In the paper it is demonstrated how a Herschel-Bulkley fluid model, where the parameters are selected from relevant shear rate range of the flow and are parametrically independent, can be used for pressure loss calculations. The model is found to provide adequate pressure loss predictions for axial flow in an annulus where the inner cylinder does not rotate. It is described how one can simplify a slot model approximation of the annulus pressure loss using the Herschel-Bulkley fluid model (Founargiotakis model). This simplified model gives approximately the same accuracy as does the full Founargiotakis model. It is shown that use of such a parallel plate model gives reasonably good fit to measured data on laminar flow of oil-based drilling fluids if the viscous data are measured at relevant shear rates for the flow. Laboratory measurements indicate that use of the simplified pressure loss model is also valid for turbulent flow. However, the predictions should be adjusted for the surface roughness in the well.

scholarly journals Microstructure and Rheological Properties of Semi-Solid 7075 Slurries Using SEED Rheocasting Process

2016 ◽  
Vol 256 ◽  
pp. 288-293 ◽  
Author(s):  
Amir Bolouri ◽  
Qin Fu Zhao ◽  
Pascal Côté ◽  
X. Grant Chen
Keyword(s):  
Rheological Properties ◽  
Grain Refinement ◽  
Parallel Plate ◽  
Grain Morphology ◽  
Transient State ◽  
High Strength ◽  
Processing Parameters ◽  
Seed Processing ◽  
Semi Solid ◽  
The Impact

The SEED rheocasting process was used to produce semisolid slurries of high strength 7075 aluminum wrought alloys. The effects of the SEED processing parameters on the microstructure of semisolid slurries were studied. The impact of grain refinement on the grain morphology and size was investigated. The rheological properties of semisolid 7075 alloys were characterized at different solid fractions using a parallel plate compression viscometer. Results indicated that the grain refinement could greatly improve the globularity of α-Al grains and rheoformability. The relationships between viscosity and shear rate at different solid fractions in the transient state for both unrefined and refined semisolid slurries were evaluated and discussed.

scholarly journals Rheology of StelliteTM 21 Alloy in Semi-Solid State

2016 ◽  
Vol 61 (4) ◽  
pp. 1901-1908 ◽  
Author(s):  
K. Sołek ◽  
P. Kapranos
Keyword(s):  
Solid State ◽  
Rheological Properties ◽  
Experimental Work ◽  
High Hardness ◽  
Measurement Methods ◽  
Viscosity Models ◽  
High Temperature Furnace ◽  
Secondary Objective ◽  
Semi Solid ◽  
Temperature Furnace

Abstract The main objective of this study was to conduct an analysis of the rheological properties of StelliteTM 21 alloy in the semi-solid state, as the results could be used for identifying the appropriate temperature range for thixoforming of this alloy, and a secondary objective of the experimental work was the development of mathematical model of the alloy’s apparent viscosity. Such viscosity models are necessary for numerical simulations of the thixoforming processes. The StelliteTM 21 alloy exhibits high hardness and thus shaping in the semi-solid state is promising route of production of parts from this alloy. Within the confines of experimental work the measurement methods of the rheological properties at high temperatures was developed. They are based on the use of specially designed viscometer equipped with high temperature furnace.

scholarly journals Effect of Yield Power Law Fluid Rheological Properties on Cuttings Transport in Eccentric Horizontal Narrow Annulus

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Titus Ntow Ofei
Keyword(s):  
Rheological Properties ◽  
Power Law ◽  
Fluid Model ◽  
Drilling Fluid ◽  
Flow Behavior ◽  
Annular Region ◽  
Cuttings Transport ◽  
Power Law Fluid ◽  
Gas Drilling ◽  
Transport Velocity

Narrow annular drilling such as casing-while-drilling technique is gaining popularity due to its ability to mitigate nonproductive time during oil and gas drilling operations. However, very little is known about the flow dynamics in narrow annular drilling. In this study, the Eulerian-Eulerian two-fluid model was used to examine the influence of Yield Power Law fluid rheological properties on cuttings transport in eccentric horizontal narrow annulus. The flow was assumed as fully developed, laminar, and transient state. The present simulation model was validated against experimental data, where a mean percent error of −1.2% was recorded. Results revealed an increase in the radial distribution of cuttings transport velocity in the wide annular region as the consistency index, K, and the flow behavior index, n, increase. Nonetheless, increasing the yield stress, τo, had insignificant effect on the cuttings transport velocity. Three-dimensional profiles showed how cuttings preferred to travel in less resistant flow area, whereas cuttings concentration builds up in the narrow annular region. Furthermore, annular frictional pressure losses also increased as K, n, and τo increased. This study serves as a guide to properly optimize drilling fluid rheological properties for efficient cuttings transport and equivalent circulating density (ECD) management in narrow annular drilling.

Enhancement of Gleditsia sinensis gum rheological properties with pressure cell treatment in semi-solid state

2016 ◽  
Vol 84 ◽  
pp. 254-260
Author(s):  
Zi-yuan Zhou ◽  
Wei-an Zhang ◽  
Jiu-fang Duan ◽  
Wei-ming Zhang ◽  
Da-feng Sun ◽  
...  
Keyword(s):  
Solid State ◽  
Rheological Properties ◽  
Pressure Cell ◽  
Gleditsia Sinensis ◽  
Semi Solid

scholarly journals Rheological Analysis of Semi-Solid A380.0 Aluminium Alloy / Analiza Właściwości Reologicznych Stopu Aluminium A380.0 W Stanie Stało-Ciekłym

2015 ◽  
Vol 60 (4) ◽  
pp. 2613-2618 ◽  
Author(s):  
K. Solek ◽  
S. Szczepanik
Keyword(s):  
Numerical Modeling ◽  
Solid State ◽  
Aluminium Alloy ◽  
Rheological Properties ◽  
Experimental Work ◽  
Liquid Aluminium ◽  
Rheological Analysis ◽  
Significant Achievement ◽  
Semi Solid ◽  
Material Tests

Knowledge of the rheological properties is crucial for the numerical modeling of technological processes. The main objective of this study was to conduct an analysis of the rheological properties of A380.0 (AlSi9Cu3(Fe)) aluminium alloy in the semi-solid state. The results could be used for identification of temperature range of the alloy, where thixoforming processes could be executed. Another purpose of the experimental work could be development of the mathematical models of the alloy apparent viscosity. The significant achievement of this particular study is an application of a viscometer which was specially designed for material tests executed at high temperatures, such as the measurement of liquid or semi-liquid aluminium viscosity. This paper presents the results of a rheological analysis of aluminium alloy.

Analysis of Rheological Properties of Steel near Solidus Point Using Gleeble® Simulator

2008 ◽  
Vol 141-143 ◽  
pp. 325-330
Author(s):  
Krzysztof P. Sołek ◽  
Zbigniew Mitura ◽  
Mirosław Karbowniczek ◽  
Plato Kapranos ◽  
Roman Kuziak ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Solid State ◽  
Liquid Phase ◽  
Rheological Properties ◽  
Wide Temperature Range ◽  
Steel Alloy ◽  
Phase Content ◽  
Globular Microstructure ◽  
Die Filling ◽  
Semi Solid

The main goal of this work is the analysis of rheological properties of steel alloy at high temperatures, just below the solidus point, and in the semi-solid state with low liquid phase content. Data obtained from the analysis can form the basis of numerical simulation for designing and optimizing the thixoforming processes. The rheological properties should be known over a wide temperature range so that the simulations could also predict defects such as incomplete die filling. The analysis concerned M2 tool steel alloy. The paper also discusses development of globular microstructure in partially melted steel.

RHEOLOGICAL PROPERTIES OF NOVEL MAGNETORHEOLOGICAL FLUIDS

2007 ◽  
Vol 21 (28n29) ◽  
pp. 4849-4857 ◽  
Author(s):  
S. MANTRIPRAGADA ◽  
X. WANG ◽  
F. GORDANINEJAD ◽  
B. HU ◽  
A. FUCHS
Keyword(s):  
Magnetic Field ◽  
Rheological Properties ◽  
Yield Stress ◽  
Parallel Plate ◽  
Magnetorheological Fluids ◽  
High Yield ◽  
Iron Particles ◽  
Shear Rates ◽  
Low Viscosity ◽  
Mr Fluids

The rheological properties of novel MR fluids are characterized using a parallel plate MR shear rheometer. In these MR fluids the surface of iron particles is coated with a polymer. The rheological properties are measured and compared at various magnetic field strengths, shear rates and strain amplitudes. It has been shown that these MR fluids exhibit stable and desirable rheological properties such as, low viscosity and high yield stress.

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