DC Plasma Synthesis of Aluminum Nitride Ceramic Powders

1990 ◽  
Vol 180 ◽  
Author(s):  
Z. P. Lu ◽  
E. Pfender
Keyword(s):  
Aluminum Nitride ◽  
Plasma Reactor ◽  
Hexagonal Phase ◽  
Ceramic Powder ◽  
Plasma Jets ◽  
Plasma Synthesis ◽  
Ceramic Powders ◽  
Fine Ceramic ◽  
Plasma Torches ◽  
Thermodynamic Equilibrium Calculations

A novel Triple DC Torch Plasma Reactor (TTPR) has been developed for the plasma synthesis of fine ceramic powders. The reactor consists of three identical plasma torches. The plasma jets from these torches form a converging plasma volume into which the starting powder is fed. Thermodynamic equilibrium calculations have been performed for predicting the behavior of an aluminum-nitrogen system. Aluminum nitride has been synthesized by using the TTPR operating in the non-transferred mode. Product characterizations indicate that single hexagonal phase AIN ceramic powder has been obtained.

Plasma Synthesis of Fine Ceramic Powders by a Novel Counter-Flow Liquid Injection Method.

1990 ◽  
Vol 180 ◽  
Author(s):  
P. Kong ◽  
T.W. Or ◽  
L. Stachowicz ◽  
E. Pfender
Keyword(s):  
Gas Phase ◽  
Material Characterization ◽  
Plasma Synthesis ◽  
Ceramic Powders ◽  
Gas Phase Reactions ◽  
Counter Flow ◽  
Standard Material ◽  
Fine Ceramic ◽  
Liquid Injection ◽  
Powder Analysis

ABSTRACTCeramic powders of carbides, oxides, solid solutions of oxides, magnetic and non-magnetic spinels, superconductors and composites have been successfully synthesized in a thermal plasma jet reactor using a novel counter-flow liquid injection plasma synthesis (CF LIPS) method developed to overcome the problems associated with solid injection and to realize the benefits of gas phase reactions and counter-flow injection. Standard material characterization techniques have been used for powder analysis.

scholarly journals Process characterization and analysis of ceramic powder bed fusion

2021 ◽  
Author(s):  
Kevin Florio ◽  
Dario Puccio ◽  
Giorgio Viganò ◽  
Stefan Pfeiffer ◽  
Fabrizio Verga ◽  
...  
Keyword(s):  
High Speed ◽  
Ceramic Powder ◽  
Integrating Sphere ◽  
Alumina Powder ◽  
Powder Bed Fusion ◽  
Single Track ◽  
Ceramic Powders ◽  
Pure Alumina ◽  
Powder Bed ◽  
Melt Pool

AbstractPowder bed fusion (PBF) of ceramics is often limited because of the low absorptance of ceramic powders and lack of process understanding. These challenges have been addressed through a co-development of customized ceramic powders and laser process capabilities. The starting powder is made of a mix of pure alumina powder and alumina granules, to which a metal oxide dopant is added to increase absorptance. The performance of different granules and process parameters depends on a large number of influencing factors. In this study, two methods for characterizing and analyzing the PBF process are presented and used to assess which dopant is the most suitable for the process. The first method allows one to analyze the absorptance of the laser during the melting of a single track using an integrating sphere. The second one relies on in-situ video imaging using a high-speed camera and an external laser illumination. The absorption behavior of the laser power during the melting of both single tracks and full layers is proven to be a non-linear and extremely dynamic process. While for a single track, the manganese oxide doped powder delivers higher and more stable absorptance. When a full layer is analyzed, iron oxide-doped powder is leading to higher absorptance and a larger melt pool. Both dopants allow the generation of a stable melt-pool, which would be impossible with granules made of pure alumina. In addition, the present study sheds light on several phenomena related to powder and melt-pool dynamics, such as the change of melt-pool shape and dimension over time and powder denudation effects.

scholarly journals Freeze injection and compression molding of fine ceramic powder by using water binder.

1987 ◽  
Vol 34 (9) ◽  
pp. 383-386 ◽  
Author(s):  
Takeo Nakagawa ◽  
Nobuyuki Takahashi ◽  
Hiroyuki Noguchi ◽  
Reiko Cho
Keyword(s):  
Ceramic Powder ◽  
Compression Molding ◽  
Fine Ceramic ◽  
Fine Ceramic Powder

Power Systems of Plasma Reactors for Non-Thermal Plasma Generation

2013 ◽  
Vol 16 (1) ◽  
Author(s):  
Henryka Danuta Stryczewska ◽  
Tomasz Jakubowski ◽  
Stanisław Kalisiak ◽  
Tomasz Giżewski ◽  
Joanna Pawłat
Keyword(s):  
Atmospheric Pressure ◽  
Arc Discharge ◽  
Plasma Reactor ◽  
Atmospheric Pressure Plasma ◽  
Plasma Jets ◽  
Plasma Reactors ◽  
Dielectric Barrier ◽  
Gliding Arc ◽  
Pressure Plasma ◽  
Supply Systems

AbstractRecently, many different plasma sources are being investigated for exhaust gases treatment, odor abatement, VOC removal, soil conditioning, surface decontamination or tissue disinfection and sterilization. Among many different plasma reactors investigated in laboratories, gliding arc discharges (GAD), dielectric barrier discharges (DBD), pulsed discharges (PD), atmospheric pressure glow discharges (APGD) and atmospheric pressure plasma jets (APPJ) seem to be the most promising for high pressure low temperature applications. They can be designed as multi-electrodes’ high power system that can be used in environment protection processes, like decontamination of large surfaces and treatment of large volume of polluted gases, as well as small size and low power devices for biomedical applications, like plasma healing, disinfection and sterilization. Paper presents review of power supply systems for cold plasma reactors. Dielectric Barrier Discharge (DBD), Gliding Arc Discharge (GAD) and atmospheric pressure plasma jet (APPJ) reactors with their supply systems have been discussed from the point view of their characteristics, possibility to control power to the discharge and efficiency. Taking into account the plasma reactor characteristics and nature (nonlinear resistive and/or capacitive) different solutions of power suppliers have been presented: transformer type, AC/DC/AC inverter, RF-frequency system and frequency resonant inverter.

scholarly journals Effects of Biceramic AlN-SiC Microparticles on the Thermal Properties of Paraffin for Thermal Energy Storage

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Arash Badakhsh ◽  
Kay-Hyeok An ◽  
Chan Woo Park ◽  
Byung-Joo Kim
Keyword(s):  
High Frequency ◽  
Interfacial Adhesion ◽  
Ceramic Powder ◽  
Efficient Production ◽  
Ceramic Powders ◽  
Short Term ◽  
Scanning Calorimetry ◽  
Characterization Methods ◽  
Thermal Features ◽  
Change Material

Herein, simplified time-efficient production of AlN-coated SiC (SiC@AlN) ceramic powder was practiced. Short-term vibratory ball milling with high frequency was employed to integrate the microsize particles. Also, paraffin as a significant phase change material (PCM) was reinforced using the manufactured SiC@AlN in order to enhance the thermal conductivity (TC) and stability of the final composite. Various characterization methods were used to clarify the changes in particle size of the biceramic powder as well as the thermal features of the paraffin-based composite. Manufactured SiC@AlN was found to be the most effective in the improvement of interfacial adhesion of composite components and the subsequent enhancement of TC, compared with singular ceramic powders as the reinforcing agents. Also, differential scanning calorimetry (DSC) indicated a very slight increase in latent heat of the fabricated composite PCM.

Basic and Hygric Properties of Concrete Containing Fine Ceramic Powder

2014 ◽  
Vol 897 ◽  
pp. 188-191 ◽  
Author(s):  
Pavel Reiterman ◽  
Ondřej Holčapek ◽  
Monika Čáchová ◽  
Filip Vogel ◽  
Marcel Jogl ◽  
...  
Keyword(s):  
Ceramic Powder ◽  
Pozzolanic Reaction ◽  
Experimental Program ◽  
Hardened Concrete ◽  
Capillary Porosity ◽  
Fine Ceramic ◽  
Powder Addition ◽  
Hygric Properties ◽  
Positive Effect ◽  
Fine Ceramic Powder

The motivation for utilization of active admixtures in concrete lies primarily in a positive effect on properties of hardened concrete with regard to its durability. Fine parts complement the grain size distribution curve, but also due to subsequent hydration arise phases with better resistance to aggressive substances from surrounding environment. Process of pozzolanic reaction is also associated with a reduction in open capillary porosity, causing a gradual reduction of the permeability of concrete. The paper presents an experimental program focused on the monitoring of evolution of basic and hygric properties of concrete with fine ceramic powder addition.

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