GAS DYNAMIC SPRAY COATINGS
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GAS DYNAMIC SPRAY (GDS)
technology is a new coating deposition process. In this process, solid powder particles are accelerated to velosities in the range of 300 to 1,200 m/sec in a supersonic gas jet. Upon impact with a substrate? these high-velocity particles plastically deform, disrupt the surface oxide layer and bond with the underlying material. GDS can be used to deposit a wide range of metals at high rates. Because the process occurs at tempera-tures much lower than the melting point of the sprayed metal powders, such materials as copper, aluminum, zinc and other ductile metals can be sprayed in an open-air environment with the little or no oxidation.
That results in the formation of very high density coatings. In addition, the GDS-deposited coatings generally contain fewer oxide impurities and less porosity that allows to form coatings with much higher thermal and electrical conductivities than in traditional, thermally sprayed coatings. TDM has exclusive rights to portable GDS equipment developed at Obninsk Center for Powder Spraying (Russia).
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GDS Advantages
- High deposition efficiencies
- Low oxide content
- High density
- High thermal & electrical conductivity
- Low residual stresses
- Minimal heat input to substrate
- Minimal grain growth - possible to retain nano-crystalline
structure
- Highly-wrought microstructure - high hardness relative to
traditional coatings
- Phase and compoditional stability
- Little masking required - averspray not a problem
- Variable spray footprint size (less than 5 mm possible,
depending on configuration)
- Minimal surface preparation for many substrates, including
Aluminum, Copper, Cast Iron and Steel
- Follows substrate contours very closely
- Excellent surface finishes are achievable
- Very short nozzle-substrate stand-offs are possible (less
than 10 mm)
GDS Applications
- Material build-up
- Surface and dimention restoration
- Leakage sealing
- Corrosion-resistant coatings
- Plastic coatings without volatile solvents
Equipment & Powder
GDS equipment is ecpecially designed to perform
the functions necessary to produce the highest quality coatings.
In some cases, this equipment can be further modified to meet
specific customer requirements for enhancing the operational
parameters of the equipment.
In addition to delivering GDS equipment possessing
unique capabilities, TDM provides customers with proprietary
powder compositions that are most suitable for both the optimal
functioning of the GDS equipment and the efficient coating deposition
process.
TDM works cooperatively with several organizations.
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DEVELOPMENT OF NEW
HIGH FREQUENCY
ACOUSTIC IMAGING SYSTEMS
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Acoustic imaging systems are used for
quantitative and imaging characterization of surface,
sub-surface and bulk materials structures. These systems
utilize acoustic impedance to produce high resolution
images of a sample's interior structure to detect "difficult-to-find"
defects, such as interfacial separa-tion, delaminations,
and various voids. Timely detecting interfacial separations
is crucial for quality control of joints formed by different
welding techniques.
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Both delaminations and voids are manufacturing
and assembly related defects that can increase the susceptibility
of components to failure in storage or use. Thus, the
acoustic microscope is becoming more and more an indispensable
diagnostic tool in the various semiconductor industry.
Especially the non-destructive investigation of encapsulated
IC's for delamination, cracks, voids and die-bonding is
one of the great advantages of ultrasonic microscope.
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TDM is engaged in development of advanced
systems and
methods in the following areas:
- Acoustic microscopy;
- High-resolution nondestructive evaluation;
- Ultrasound sensors;
- Array transducers;
- Acousto-optics;
- etc.
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LASER ACOUSTIC SHAPE
MEASUREMENT SYSTEM
- Short-pulse laser with 5...10^-2 J/cm2
energy and pulse duration 10-7s;
- Up to 8 microphones for higher accuracy;
- 70 micron resolution at distances of
0.7–1.0 m between microphones and object;
- Up to 5 points per second measurement
speed;
- Light weight (12 kg), easy to use, easy
to transport prototype
Laser Acoustic Shape Measurement System
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