Low Temperature Metal Coating Method

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Low Temperature Metal Coating Method

B. Background
A new metal coating method, called KEM (kinetic energy metallization), demonstrated
in the laboratory by Inovati, utilized fast-moving solid particles entrained in a gas that
are caused to flow through a nozzle to effect particle deposition on metal surfaces at
room temperature conditions. This method (US Patent 5,795,626) was an attractive and
viable alternative to the currently available high-temperature coating methods
available.
Since it differs significantly from existing metal coating technologies, a brief description
of the method is included here. The proposed method, KEM, achieves cohesive and
adhesive metallurgical bonding through the high-speed collision of powder with a
substrate and the subsequent discharge of electrical charge at the substrate. Such
coating is effected by entraining metal powder in a gas and accelerating this mixture
through a supersonic nozzle. The gas/powder is directed towards the substrate to be
coated. Collisions occur, initially between the powder and the substrate, and, as the first
layer of the coating forms, between the powder and the coating. During these collisions
the powder is rapidly deformed, causing the exposure of fresh (oxide free) active metal
surface. When these active surfaces contact one another, they agglomerate and form
true metallurgical bonds. The resultant coating has low porosity and high adhesive and
cohesive strength. The formation of metallurgical bonds is potentiated by the discharge
of electrical energy. This electrical energy is the result of triboelectric charging of the
particles during acceleration and transit to the nozzle.
An advantage of the method is that it does not raise the temperature of the powder
being applied or that of the substrate. Consequently, materials sensitive to high
temperature may be applied without changing the properties of the material or
substrate.

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Reasons for Cooperation:
• LLNL Need: The Weaponization Program was interested in the method,
especially as an inexpensive and efficient way of depositing Uranium for
nuclear weapon refurbishment.
• Inovati Expertise/Need: Inovati demonstrated that metal deposition could
indeed take place through the method. However, Inovati lacked analytical
capabilities to address the fundamental physics of KEM.
• LLNL Expertise: LLNL possessed expertise in theoretically addressing the
two-phase flow dynamics and the interaction phenomena between the
impacting particles and the target material.
C. Description
The purpose of the program for LLNL was to gain an understanding of the physical
factors involved when high-velocity metal particles impinge on a metal surface. Insight
thus obtained would aid in optimizing the metal-deposition operating conditions.
For the industrial partner, the purpose was to experimentally demonstrate the relevance
and applicability of the method to the LLNL Weaponization Program, especially Udeposition
for nuclear weapon refurbishment.

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D. Expected Economic Impact
The LLNL theoretical analyses of the underlying physics involved in metal deposition
with gas/solid nozzle flows would enable Inovati to optimize the operating conditions,
and allow for the low-cost development of the KEM product. The work would have a
major impact on the time required to move this technology from the laboratory to the
marketplace.
When introduced to the marketplace, KEM will provide a lower cost (both acquisition
and life cycle cost) alternative to conventional coating processes. Subsequent to this
work KEM has proved to be a viable alternative to certain laser assisted deposition,
thermal spray, vapor deposition, and chemical and electrochemical platting processes.
KEM is under evaluation to replace these processes because it is cheaper and produces
none of the environmental hazards associated with them.
KEM is expected to help maintain the U.S. leadership in metal coating technology. This
leadership role has resided in the United States for over 50 years though new
developments are increasingly originating in Europe and Japan.

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E. Benefits to DOE
Laboratory Program core competencies: The theoretical analyses (LLNL) and tests
(Inovati) had direct impact on U-deposition for nuclear weapon refurbishment project
currently under way at LLNL as a part of the LLNL Weaponization Program. The
cognizant personnel at LLNL expressed specific interest in this proposal as a very viable
alternative to some traditional metal deposition technologies that were becoming
increasingly unattractive due to high cost and environmental constraints.
Another way in which the proposed method enhanced the LLNL weapons core
competencies was its application for the long-term storage strategies of radioactive
weapons components that call for encapsulation with metal.
DOE/Defense Programs: The method has wide applicability to the Defense Program
Missions and Critical Technologies, notably material welding and fabrication connected
to the material science and technology, national ignition facility, factory of future and
systems engineering and manufacturing technologies.

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2/17/00
E. Benefits to DOE
Laboratory Program core competencies: The theoretical analyses (LLNL) and tests
(Inovati) had direct impact on U-deposition for nuclear weapon refurbishment project
currently under way at LLNL as a part of the LLNL Weaponization Program. The
cognizant personnel at LLNL expressed specific interest in this proposal as a very viable
alternative to some traditional metal deposition technologies that were becoming
increasingly unattractive due to high cost and environmental constraints.
Another way in which the proposed method enhanced the LLNL weapons core
competencies was its application for the long-term storage strategies of radioactive
weapons components that call for encapsulation with metal.
DOE/Defense Programs: The method has wide applicability to the Defense Program
Missions and Critical Technologies, notably material welding and fabrication connected
to the material science and technology, national ignition facility, factory of future and
systems engineering and manufacturing technologies.
F. Industry Area
The transportation and electronics industries are the focus of KEM commercialization
efforts. Products for these industries are now under development with the help of two
DOD and one DOE sponsored research projects. Private industry is providing matching
funds in support of this research. Through this work commercialization is expected
within two years.
Inovati has installed a KEM system in the Thermal Spray Laboratory at the State
University of New York, Stony Brook, where additional research and characterization
of the system is taking place.
G. Project Status
This was a four-month CRADA. It was completed in October 1996.
Sang-Wook Kang, L-140
Tel: (510) 422-7233
Fax: (510) 422-5397
email: kang1@llnl.gov

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I. Company Size and Point(s) of Contact
Inovati annual sales are less than $5 million, and the company employs less than 20
people.
Howard Gabel
President
Tel: (805) 571-8384
Fax: (805) 571-6200
email: hgabel@inovati.com
www: http://www.inovati.com
CRADA TSB-1155-95 Page 4
PAS
2/17/00
J. Project Examples
None
K. Intellectual Property
Subject Inventions:
CRADA Article I defines a Subject Invention as any invention of LLNL or
Participant conceived or first actually reduced to practice in the performance of
work under this CRADA. CRADA Article XIII requires each Party to disclose to
the other every Subject Invention, and provides that the inventing Party has first
option to retain title to any Subject Invention made by its employees during work
under this CRADA.
LLNL Subject Inventions: None
Participant Subject Inventions: None
Copyright:
CRADA Article X provides that each party may assert copyright in its Generated
Information, including computer software and documentation produced under
this CRADA.
LLNL computer software/documentation: None
Participant computer software/documentation: None
L. Release of Information
I certify that all information contained in this report is accurate and releasable to the
best of my knowledge.
Karena McKinley, Director Date
Industrial Partnerships
and Commercialization
RELEASE OF INFORMATION
I have reviewed the attached Project Accomplishment Summary prepared by Lawrence
Livermore National Laboratory and agree that the information about our CRADA may
be released for external distribution.