New Developments in the Plasma Transferred Arc Process

1997 ◽  
Author(s):  
R.J. DuMola ◽  
G.R. Heath
Keyword(s):  
High Performance ◽  
Power Utility ◽  
Small Areas ◽  
Powder Alloys ◽  
Plasma Transferred Arc ◽  
Transferred Arc ◽  
Recent Developments ◽  
Coating Method ◽  
And Performance ◽  
New Applications

Abstract The plasma transferred arc process continues to be the coating method of choice for the application of cobalt base alloys onto valve and valve trim. Although new applications have been developed over the years, the process remains largely associated with the application of high performance, highly alloyed powders for relatively small parts or small areas of large parts. The use of the plasma transferred arc process for large volume application has been limited by the robustness and performance characteristics of the equipment and the use of cobalt. A new plasma transferred arc system (power source, torch and process controller) has been developed which allows the application of powder metal alloys at deposition rates of up to 40 pounds per hour. In addition, there has been a development of new non-cobalt powder alloys with excellent mixed corrosion and wear resistance properties. These capabilities have rendered the process technically and economically viable for large and demanding applications in the mining, power utility and steel industries. The new PTA system and the recent developments in powder alloys will be discussed. Reference will be made to specific applications in target industries.

scholarly journals Application of digital micromirror devices (DMD) in biomedical instruments

2020 ◽  
Vol 13 (06) ◽  
pp. 2030011
Author(s):  
Ziyun Zhuang ◽  
Ho Pui Ho
Keyword(s):  
High Performance ◽  
Response Speed ◽  
Micro Electro Mechanical System ◽  
Light Modulator ◽  
Biomedical Sensing ◽  
Recent Developments ◽  
Bio Imaging ◽  
Digital Micromirror Devices ◽  
Economic Developments ◽  
New Applications

There is an ongoing technological revolution in the field of biomedical instruments. Consequently, high performance healthcare devices have led to remarkable economic developments in the medical hardware industry. Until now, nearly all optical bio-imaging systems are based on the 2-dimensional imaging chip architecture. In fact, recent developments in digital micromirror devices (DMDs) are gradually making their way from conventional optical projection displays into biomedical instruments. As an ultrahigh-speed spatial light modulator, the DMD may offer a range of new applications including real-time biomedical sensing or imaging, as well as orientation tracking and targeted screening. Given its short history, the use of DMD in biomedical and healthcare instruments has emerged only within the past decade. In this paper, we first provide an overview by summarizing all reported cases found in the literature. We then critically analyze the general pros and cons of using DMD, specifically in terms of response speed, stability, accuracy, repeatability, robustness, and degree of automation, in relation to the performance outcome of the designated instrument. Particularly, we shall focus our discussion on the use of Micro-Electro-Mechanical System (MEMS)-based devices in a set of representative instruments including the surface plasmon resonance biosensor, optical microscopes, Raman spectrometers, ophthalmoscopes, and the micro stereolithographic system. Finally, the prospects of using the DMD approach in biomedical or healthcare systems and possible next generation DMD-based biomedical devices are presented.

scholarly journals Refining Atmosphere Profiles for Aerial Target Detection Models

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7067
Author(s):  
Robert Grimming ◽  
Patrick Leslie ◽  
Derek Burrell ◽  
Gerald Holst ◽  
Brian Davis ◽  
...  
Keyword(s):  
System Performance ◽  
High Performance ◽  
Geographic Location ◽  
Weather Conditions ◽  
Atmospheric Composition ◽  
Quality Data ◽  
Average System ◽  
Atmospheric Path ◽  
And Performance ◽  
New Applications

Atmospheric path radiance in the infrared is an extremely important quantity in calculating system performance in certain infrared detection systems. For infrared search and track (IRST) system performance calculations, the path radiance competes with the target for precious detector well electrons. In addition, the radiance differential between the target and the path radiance defines the signal level that must be detected. Long-range, high-performance, offensive IRST system design depends on accurate path radiance predictions. In addition, in new applications such as drone detection where a dim unresolved target is embedded into a path radiance background, sensor design and performance are highly dependent on atmospheric path radiance. Being able to predict the performance of these systems under particular weather conditions and locations has long been an important topic. MODTRAN has been a critical tool in the analysis of systems and prediction of electro-optical system performance. The authors have used MODTRAN over many years for an average system performance using the typical “pull-down” conditions in the software. This article considers the level of refinement required for a custom MODTRAN atmosphere profile to satisfactorily model an infrared camera’s performance for a specific geographic location, date, and time. The average difference between a measured sky brightness temperature and a MODTRAN predicted value is less than 0.5 °C with sufficient atmosphere profile updates. The agreement between experimental results and MODTRAN predictions indicates the effectiveness of including updated atmospheric composition, radiosonde, and air quality data from readily available Internet sources to generate custom atmosphere profiles.

Trace nanoanalysis

1994 ◽  
Vol 52 ◽  
pp. 940-941
Author(s):  
D. E. Newbury ◽  
R. D. Leapman
Keyword(s):  
High Performance ◽  
Secondary Ion Mass Spectrometry ◽  
Detection Efficiency ◽  
Volume Element ◽  
And Performance ◽  
Trace Constituents ◽  
Secondary Ion ◽  
Concentration Levels ◽  
Structure Properties

Trace constituents, which can be very loosely defined as those present at concentration levels below 1 percent, often exert influence on structure, properties, and performance far greater than what might be estimated from their proportion alone. Defining the role of trace constituents in the microstructure, or indeed even determining their location, makes great demands on the available array of microanalytical tools. These demands become increasingly more challenging as the dimensions of the volume element to be probed become smaller. For example, a cubic volume element of silicon with an edge dimension of 1 micrometer contains approximately 5×1010 atoms. High performance secondary ion mass spectrometry (SIMS) can be used to measure trace constituents to levels of hundreds of parts per billion from such a volume element (e. g., detection of at least 100 atoms to give 10% reproducibility with an overall detection efficiency of 1%, considering ionization, transmission, and counting).

Microstructure of sputter deposited Ni-Sb ohmic contacts on GaAs

1989 ◽  
Vol 47 ◽  
pp. 450-451
Author(s):  
S. Yegnasubramanian ◽  
V.C. Kannan ◽  
R. Dutto ◽  
P.J. Sakach
Keyword(s):  
High Performance ◽  
Ohmic Contacts ◽  
Surface Defects ◽  
Pure Metal ◽  
Device Fabrication ◽  
Native Oxide ◽  
Metal Thin Films ◽  
Recent Developments ◽  
Different Temperatures ◽  
Sputter Deposited

Recent developments in the fabrication of high performance GaAs devices impose crucial requirements of low resistance ohmic contacts with excellent contact properties such as, thermal stability, contact resistivity, contact depth, Schottky barrier height etc. The nature of the interface plays an important role in the stability of the contacts due to problems associated with interdiffusion and compound formation at the interface during device fabrication. Contacts of pure metal thin films on GaAs are not desirable due to the presence of the native oxide and surface defects at the interface. Nickel has been used as a contact metal on GaAs and has been found to be reactive at low temperatures. Formation Of Ni2 GaAs at 200 - 350C is reported and is found to grow epitaxially on (001) and on (111) GaAs, but is shown to be unstable at 450C. This paper reports the investigations carried out to understand the microstructure, nature of the interface and composition of sputter deposited and annealed (at different temperatures) Ni-Sb ohmic contacts on GaAs by TEM. Attempts were made to correlate the electrical properties of the films such as the sheet resistance and contact resistance, with the microstructure. The observations are corroborated by Scanning Auger Microprobe (SAM) investigations.

The mechanism of spraying of paraffin-based fuel by using of plasma transferred arc

2017 ◽  
Vol 23 (1) ◽  
pp. 30-35
Author(s):  
L.A. Bulavin ◽  
◽  
V.Ya. Chernyak ◽  
L.Yu. Vergun ◽  
Yu.F. Zabashta ◽  
...  
Keyword(s):  
Plasma Transferred Arc ◽  
Transferred Arc

What Can Digitization Do For Formulated Product Innovation and Development

2020 ◽  
Author(s):  
James McDonagh ◽  
William Swope ◽  
Richard L. Anderson ◽  
Michael Johnston ◽  
David J. Bray
Keyword(s):  
High Performance ◽  
Quality Data ◽  
High Quality Data ◽  
Base Level ◽  
Hybrid Approaches ◽  
Digital Ecosystem ◽  
Recent Developments ◽  
Chemical Simulation ◽  
High Level ◽  
Physical And Chemical

Digitization offers significant opportunities for the formulated product industry to transform the way it works and develop new methods of business. R&D is one area of operation that is challenging to take advantage of these technologies due to its high level of domain specialisation and creativity but the benefits could be significant. Recent developments of base level technologies such as artificial intelligence (AI)/machine learning (ML), robotics and high performance computing (HPC), to name a few, present disruptive and transformative technologies which could offer new insights, discovery methods and enhanced chemical control when combined in a digital ecosystem of connectivity, distributive services and decentralisation. At the fundamental level, research in these technologies has shown that new physical and chemical insights can be gained, which in turn can augment experimental R&D approaches through physics-based chemical simulation, data driven models and hybrid approaches. In all of these cases, high quality data is required to build and validate models in addition to the skills and expertise to exploit such methods. In this article we give an overview of some of the digital technology demonstrators we have developed for formulated product R&D. We discuss the challenges in building and deploying these demonstrators.<br>

Microstructure and Microhardness Characterization of Cr3C2-SiC Coatings Produced by the Plasma Transferred Arc Method

2012 ◽  
Vol 54 (11-12) ◽  
pp. 793-799 ◽  
Author(s):  
Serkan Islak ◽  
Özkan Eski ◽  
Soner Buytoz ◽  
Muzaffer Karagöz ◽  
Joseph Stokes
Keyword(s):  
Plasma Transferred Arc ◽  
Transferred Arc ◽  
Sic Coatings

COLMONOY No. 83 PTA

Alloy Digest ◽  
1995 ◽  
Vol 44 (12) ◽  
Keyword(s):  
Wear Resistance ◽  
Compressive Strength ◽  
Physical Properties ◽  
Tungsten Carbide ◽  
Tensile Properties ◽  
Powder Metal ◽  
Application Method ◽  
Plasma Transferred Arc ◽  
Transferred Arc ◽  
Nickel Base

Abstract COLMONOY No. 83 PTA is a nickel-base hard surfacing alloy containing tungsten carbide. The application method is plasma transferred arc and the application is designed to protect extrusion screws. This datasheet provides information on composition, physical properties, microstructure, hardness, tensile properties, and compressive strength. It also includes information on wear resistance as well as machining and powder metal forms. Filing Code: Ni-493. Producer or source: Wall Colmonoy Corporation.

Sign in / Sign up

Export Citation Format

Share Document