scholarly journals Simulation Fluidity Test for Semisolid Squeeze Casting

2020 ◽  
Vol 328 ◽  
pp. 02006
Author(s):  
Richard Pastirčák ◽  
Denis Martinec
Keyword(s):  
Squeeze Casting ◽  
Solid Phase ◽  
Mold Temperature ◽  
Simulation Software ◽  
Operating Pressure ◽  
Piston Speed ◽  
Solid Phase Content ◽  
Semi Solid ◽  
Test Casting ◽  
The Individual

The paper deals with semi solid squeeze casting technology. Fluidity tests were designed for the selected technology. The shape of the test casting was designed in the shape of test bars with different thicknesses and also in the shape of a stepped casting. The thickness of the individual elements was chosen on the basis of a selected / preferred numbers R10 EN STN 17. As a result, the thickness of the elements was 2.0, 2.5, 3.15, 4.0, 5.0 and 6.3 mm. Designed fluidity tests were verified by using ProCast simulation software. The selected process parameters were: operating pressure 80 MPa, mold temperature 200 °C, piston speed 30 mm.s-1. The experimental material was an AlSi7Mg0.3 alloy with a different solid phase content. The initial solid amount were 50, 55 and 60 %. The effect of solidus and liquidus, temperature distribution and pressure was monitored during the evaluation of fluidity.

Effect of Runner Distance on Microstructure and Properties of Semi-Solid Squeeze Casting CuSn10P1 Alloy

2022 ◽  
Vol 327 ◽  
pp. 156-162
Author(s):  
Yong Kun Li ◽  
Pei Lin Cai ◽  
Zhi Long He ◽  
Rong Feng Zhou ◽  
Lu Li ◽  
...  
Keyword(s):  
Squeeze Casting ◽  
Solid Phase ◽  
High Strength ◽  
Shrinkage Porosity ◽  
Microstructure And Properties ◽  
Shrinkage Defects ◽  
Porosity Defects ◽  
Semi Solid ◽  
Slope Channel ◽  
Better Than

It is easy to form reverse segregation and shrinkage porosity defects during the solidification of CuSn10P1 alloy, which leads to the poor properties and limits its application in high strength and toughness parts. In this paper, semi-solid CuSn10P1 alloy slurry was prepared by enclosed cooling slope channel (for short ECSC). The effect of runner distance on microstructure and properties by liquid squeeze casting and semi-solid squeeze casting was studied. The results showed that the microstructure of semi-solid squeeze casting is finer than that of liquid squeeze casting, and the shrinkage defects are improved. The solid fraction with 65 mm runner is lower than that without runner in liquid squeeze casting and semi-solid squeeze casting due to the retention effect of solid phase in semi-solid slurry flow, but the properties with 65 mm runner is better than that without runner. The ultimate tensile strength, yield strength and elongation of semi-solid squeeze casting CuSn10P1 alloy with 65 mm runner distance reached 466.5 MPa, 273.6 MPa and 13.4%, which were improved by 26%, 19% and 97%, respectively, as compared to that of liquid squeeze casting.

scholarly journals The Effects of Pressure During the Crystallization on Properties of the AlSi12 Alloy

2017 ◽  
Vol 17 (3) ◽  
pp. 103-106 ◽  
Author(s):  
R. Pastirčák ◽  
J. Ščury ◽  
J. Moravec
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Squeeze Casting ◽  
Structural Characteristics ◽  
Mold Temperature ◽  
Operating Pressure ◽  
Technological Parameters ◽  
Casting Method ◽  
A Value ◽  
The Impact

Abstract The paper deals with the impact of technological parameters on the mechanical properties and microstructure in AlSi12 alloy using squeeze casting technology. The casting with crystallization under pressure was used, specifically direct squeeze casting method. The goal was to affect crystallization by pressure with a value 100 and 150 MPa. From the experiments we can conclude that operating pressure of 100 MPa is sufficient to influence the structural characteristics of the alloy AlSi12. The change in cooling rate influences the morphology of the silicon particles and intermetallic phases. A change of excluded needles to a rod-shaped geometries with significantly shorter length occurs when used gravity casting method. At a pressure of 100 MPa was increased of tensile strength on average of 20%. At a pressure of 150 MPa was increased of tensile strength on average of 30%. During the experiment it was also observed, that increasing difference between the casting temperature and the mold temperature leads to increase of mechanical properties.

scholarly journals Simulation of solidification during crystallization under pressure

2018 ◽  
Vol 157 ◽  
pp. 02035
Author(s):  
Richard Pastirčák ◽  
Marek Brůna ◽  
Dana Bolibruchová
Keyword(s):  
Mechanical Properties ◽  
Squeeze Casting ◽  
Mold Temperature ◽  
Simulation Software ◽  
Influence Of Process Parameters ◽  
Casting Technology ◽  
Crystallization Under Pressure ◽  
Shape Influence ◽  
Sample Width ◽  
Gravity Cast

The paper deals with squeeze casting technology. The influence of process parameters variation (casting temperature, mold temperature, pressure) will be observed. The experimentally obtained boundary conditions (heat flow, HTC) will be verified using the ProCast simulation software. Shape influence on the mold filling process and the temperature field under pressure will be evaluated. To evaluate the mechanical properties, a tensile test was performed. Three identical samples were cast for each parameters change. From these samples the average values of the mechanical properties were measured and calculated. The thickness of the flat test samples was 3.15, 4, 5, 6.3, 8 mm with a sample width of 10 mm. For gravity cast of the casting, the mechanical properties of the thinner parts were higher. At the pressure influenced castings, the mechanical properties were higher in the thicker parts of the casting.

Fully Automated Parallel Oligonucleotide Synthesizer

2001 ◽  
Vol 66 (8) ◽  
pp. 1299-1314 ◽  
Author(s):  
Michal Lebl ◽  
Christine Burger ◽  
Brett Ellman ◽  
David Heiner ◽  
Georges Ibrahim ◽  
...  
Keyword(s):  
Solid Phase ◽  
Building Blocks ◽  
Solid Support ◽  
Continuous Operation ◽  
Gear Pump ◽  
Oligonucleotide Synthesis ◽  
Center Of Rotation ◽  
Microtiter Plates ◽  
The Individual ◽  
Design And Construction

Design and construction of automated synthesizers using the tilted plate centrifugation technology is described. Wash solutions and reagents common to all synthesized species are delivered automatically through a 96-channel distributor connected to a gear pump through two four-port selector valves. Building blocks and other specific reagents are delivered automatically through banks of solenoid valves, positioned over the individual wells of the microtiterplate. These instruments have the following capabilities: Parallel solid-phase oligonucleotide synthesis in the wells of polypropylene microtiter plates, which are slightly tilted down towards the center of rotation, thus generating a pocket in each well, in which the solid support is collected during centrifugation, while the liquid is expelled from the wells. Eight microtiterplates are processed simultaneously, providing thus a synthesizer with a capacity of 768 parallel syntheses. The instruments are capable of unattended continuous operation, providing thus a capacity of over two millions 20-mer oligonucleotides in a year.

scholarly journals Polymer Binders of Ceramic Nanoparticles for Precision Casting of Nickel-Based Superalloys

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1714
Author(s):  
Paweł Wiśniewski
Keyword(s):  
Solid Phase ◽  
Average Particle Size ◽  
Water Soluble ◽  
Ethyl Silicate ◽  
Average Particle ◽  
Precision Casting ◽  
Polymer Binders ◽  
Initial Stage ◽  
Nano Alumina ◽  
Solid Phase Content

This study presents the general characteristics of binders used in precision casting of Nickel-based superalloys. Three groups of binders were described: resins, organic compounds, and materials containing nanoparticles in alcohol or aqueous systems. This study also includes literature reports on materials commonly used and those recently replaced by water-soluble binders, i.e., ethyl silicate (ES) and hydrolysed ethyl silicate (HES). The appearance of new and interesting solutions containing nano-alumina is described, as well as other solutions at the initial stage of scientific research, such as those containing biopolymers, biodegradable polycaprolactone (PCL), or modified starch. Special attention is paid to four binders containing nano-SiO2 intended for the first layers (Ludox AM, Ludox SK) and structural layers (EHT, Remasol) of shell moulds. Their morphology, viscosity, density, reactions, and electrokinetic potential were investigated. The binders were characterized by a high solid-phase content (>28%), viscosity, and density close to that of water (1–2 mPa·s) and good electrokinetic stability. The nanoparticles contained in the binders were approximately spherically shaped with an average particle size of 16–25 nm.

Effect of Pouring Temperature and Holding Time at Semi-Solid Region on the Morphology of Primary Solid Phase in Semi-Solid Slurry

2006 ◽  
Vol 510-511 ◽  
pp. 782-785 ◽  
Author(s):  
Suk Won Kang ◽  
Ki Bae Kim ◽  
Dock Young Lee ◽  
Jung-Hwa Mun ◽  
Eui Pak Yoon
Keyword(s):  
Solid Phase ◽  
Holding Time ◽  
Pouring Temperature ◽  
Solid Region ◽  
Semi Solid

Microstructure and Mechanical Properties of Mg-6Zn-1.4Y Alloy Produced by Rheo-Squeeze Casting Process

2016 ◽  
Vol 879 ◽  
pp. 530-535
Author(s):  
Xiao Gang Fang ◽  
Shu Sen Wu ◽  
Shu Lin Lü
Keyword(s):  
Mechanical Properties ◽  
Power Density ◽  
Squeeze Casting ◽  
Casting Process ◽  
Acoustic Power ◽  
Icosahedral Quasicrystal ◽  
Microstructure And Mechanical Properties ◽  
Average Grain Size ◽  
Grain Size And Shape ◽  
Semi Solid

Mg-Zn-Y alloys containing a thermally stable icosahedral quasicrystal phase (I-phase) will have wide application future on condition that primary α-Mg dendrite and the I-phase can be refined during the casting process. In this research, the microstructure and mechanical properties of the rheo-squeeze casting (RSC) Mg-6Zn-1.4Y alloys have been investigated. The Mg alloy melt was exposed to ultrasonic vibration (USV) with different acoustic power densities from 0 W/mL to 9 W/mL, and then the slurry was formed by squeeze casting. The results show that good semi-solid slurry with fine and spherical α-Mg particles could be obtained with the acoustic power density of 6 W/mL, and the average grain size and shape factor of primary α-Mg were 32 μm and 0.76, respectively. Meanwhile the coarse eutectic I-phase (Mg3Zn6Y) was refined obviously and dispersed uniformly. Compared with the samples without USV, the tensile strength and elongation of the RSC casting samples with 6 W/mL acoustic power density were elevated by 10.6% and 55.5%, respectively.

scholarly journals Micro Salting-Out Assisted Matrix Solid-Phase Dispersion: A Simple and Fast Sample Preparation Method for the Analysis of Bisphenol Contaminants in Bee Pollen

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2350
Author(s):  
Jianing Zhang ◽  
Fengjie Yu ◽  
Yunmin Tao ◽  
Chunping Du ◽  
Wenchao Yang ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Preparation Method ◽  
Solid Phase ◽  
Sample Preparation Method ◽  
Salting Out ◽  
Bee Pollen ◽  
Matrix Solid Phase Dispersion ◽  
Phase Dispersion ◽  
New Strategy ◽  
Semi Solid

In the present work, a novel sample preparation method, micro salting-out assisted matrix solid-phase dispersion (μ-SOA-MSPD), was developed for the determination of bisphenol A (BPA) and bisphenol B (BPB) contaminants in bee pollen. The proposed method was designed to combine two classical sample preparation methodologies, matrix solid-phase dispersion (MSPD) and homogenous liquid-liquid extraction (HLLE), to simplify and speed-up the preparation process. Parameters of μ-SOA-MSPD were systematically investigated, and results indicated the significant effect of salt and ACN-H2O extractant on the signal response of analytes. In addition, excellent clean-up ability in removing matrix components was observed when primary secondary amine (PSA) sorbent was introduced into the blending operation. The developed method was fully validated, and the limits of detection for BPA and BPB were 20 μg/kg and 30 μg/kg, respectively. Average recoveries and precisions were ranged from 83.03% to 94.64% and 1.76% to 5.45%, respectively. This is the first report on the analysis of bisphenol contaminants in bee pollen sample, and also on the combination of MSPD and HLLE. The present method might provide a new strategy for simple and fast sample preparation of solid and semi-solid samples.

scholarly journals Predicting the glass transition temperature and viscosity of secondary organic material using molecular composition

2018 ◽  
Vol 18 (9) ◽  
pp. 6331-6351 ◽  
Author(s):  
Wing-Sy Wong DeRieux ◽  
Ying Li ◽  
Peng Lin ◽  
Julia Laskin ◽  
Alexander Laskin ◽  
...  
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Chemical Composition ◽  
Organic Compounds ◽  
Molar Mass ◽  
Solid Phase ◽  
Amorphous Solid ◽  
Semi Solid ◽  
Oxygen Atoms

Abstract. Secondary organic aerosol (SOA) accounts for a large fraction of submicron particles in the atmosphere. SOA can occur in amorphous solid or semi-solid phase states depending on chemical composition, relative humidity (RH), and temperature. The phase transition between amorphous solid and semi-solid states occurs at the glass transition temperature (Tg). We have recently developed a method to estimate Tg of pure compounds containing carbon, hydrogen, and oxygen atoms (CHO compounds) with molar mass less than 450 g mol−1 based on their molar mass and atomic O : C ratio. In this study, we refine and extend this method for CH and CHO compounds with molar mass up to ∼ 1100 g mol−1 using the number of carbon, hydrogen, and oxygen atoms. We predict viscosity from the Tg-scaled Arrhenius plot of fragility (viscosity vs. Tg∕T) as a function of the fragility parameter D. We compiled D values of organic compounds from the literature and found that D approaches a lower limit of ∼ 10 (±1.7) as the molar mass increases. We estimated the viscosity of α-pinene and isoprene SOA as a function of RH by accounting for the hygroscopic growth of SOA and applying the Gordon–Taylor mixing rule, reproducing previously published experimental measurements very well. Sensitivity studies were conducted to evaluate impacts of Tg, D, the hygroscopicity parameter (κ), and the Gordon–Taylor constant on viscosity predictions. The viscosity of toluene SOA was predicted using the elemental composition obtained by high-resolution mass spectrometry (HRMS), resulting in a good agreement with the measured viscosity. We also estimated the viscosity of biomass burning particles using the chemical composition measured by HRMS with two different ionization techniques: electrospray ionization (ESI) and atmospheric pressure photoionization (APPI). Due to differences in detected organic compounds and signal intensity, predicted viscosities at low RH based on ESI and APPI measurements differ by 2–5 orders of magnitude. Complementary measurements of viscosity and chemical composition are desired to further constrain RH-dependent viscosity in future studies.

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