Kahaner Report: Ceramic processing activities
Rick Schlichting
Office of Naval Research-Asia (ONR Asia) in Tokyo from NIST. The
following is the professional opinion of David Kahaner and in no
way has the blessing of the US Government or any agency of it. All
information is dated and of limited life time. This disclaimer should
be noted on ANY attribution.]
[Copies of previous reports written by Kahaner can be obtained using
anonymous FTP from host cs.arizona.edu, directory japan/kahaner.reports.]
From:
Dr. David K. Kahaner
US Office of Naval Research Asia
(From outside US): 23-17, 7-chome, Roppongi, Minato-ku, Tokyo 106 Japan
(From within US): Unit 45002, APO AP 96337-0007
Tel: +81 3 3401-8924, Fax: +81 3 3403-9670
Email: kah...@cs.titech.ac.jp
Re: Ceramic processing and functionally graded materials activities
in some Japanese national and semi-public laboratories
09/26/94 (MM/DD/YY)
This file is named "j-ceram.94"
ABSTRACT. The body of a report on the state of ceramic processing and
functionally graded materials research in Japanese national and
semi-public laboratories, based on visits to Japan 6-14 June 1994 by
scientists from two US companies (Saint-Gobain/Norton Industrial
Ceramics and AlliedSignal) and a US national lab (National Institute of
Standards and Technology).
The following report was written by the team members listed below. I
wish to thank Dr. J. Carpenter for his assistance in preparing this copy
for electronic distribution, in a somewhat abbreviated form. The focus
of the team's efforts was to examine the areas of (1) ceramic
processing, and (2) functionally graded materials research in Japan, and
to identify areas of possible collaboration between US and Japanese
researchers, especially those in or associated with AIST labs. (Item (2)
refers to materials in which the spatial composition and/or property
changes are deliberately gradual.) The attached report was one of three;
two other reports are being prepared by other groups in distinct
technology areas, scientific databases and biotechnology.
Report of Study Team on Ceramics Processing
and Functionally Graded Materials (shortened version)
July 20, 1994
INTRODUCTION
This is a report on the visits of (hereinafter designated as) the
Materials Team (MT) associated with (US Department of Commerce (DOC)
Under Secretary for Technology) Dr. Mary Good's official visit to Japan
the week of June 6 through June 10, 1994 for talks culminating in an
agreement on cooperative research between the DOC's National Institute
of Standards and Technology (NIST) and Japanese laboratories under the
authority of the Agency of Industrial Science and Technology (AIST) of
the Ministry of International Trade and Industry (MITI). Two other
study groups, one on scientific and technical data and databases
(hereinafter designated the Data Team, or DT) and another on
biotechnology, were also visiting Japan at the same time in association
with Dr. Good's official visit and have submitted separate reports.
The MT members were:
Dr. Joseph A. Carpenter, Jr., Ceramics Division, NIST,
Gaithersburg, MD 20899 (Team Leader),
Tel: (301) 975-6397, -6119; Fax: (301) 990-8729
Email: car...@micf.nist.gov
Dr. Vimal K. Pujari, Saint-Gobain/Norton Industrial Ceramics
Corporation, Northboro, MA, and
Dr. Philip Whalen, AlliedSignal Research and Technology
Corporation, Morristown, NJ
Each is briefly profiled at the end of this report.
The MT's general, overall mission was to study the technical areas of
ceramics processing (weighted more toward structural than functional
applications) and functionally graded materials (a Japanese-coined term
meaning materials in which the spatial composition and/or property
changes are deliberately gradual).
DETAILS
Nagoya
On Monday, June 6, the MT visited the Japan Fine Ceramics Center (JFCC)
and on Tuesday, June 7, the AIST National Industrial Research Institute
of Nagoya (NIRIN). Dr. Gary Mallard from the DT joined the NIRIN visit.
The MT was shepherded to these visits by Dr. Takeshi Takayanagi of
NIRIN, who also arranged a special tour of the Noritake Ceramics
(tableware, etc.) plant in Nagoya on the afternoon of June 7. On the
evening of Monday, June 6, the MT had dinner with NIRIN personnel.
Nagoya is the unofficial capital of the Chubu region where much of the
ancient Japanese ceramic art sprang up and where much of modern Japan's
traditional (* see below) ceramics industry is located. Traditional
ceramics was one of the first areas targeted by Japan for increased
foreign trade after World War II.
(* The term "traditional ceramics," as used in both Japan and the US,
refers to such products as pottery, china, and sanitary wares or
whitewares, as opposed to modern, high-technology, engineering ceramics
for which the term "advanced ceramics" is used in the US and the term
"fine ceramics" is used in Japan.)
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Japan Fine Ceramics Center (JFCC):
The MT was hosted by two young researchers, Mr. Osamu Hayakawa and Mr.
Fukuda.
The JFCC was established in 1985 and began operation in 1987 as a
national center for research and development, testing, inspection,
evaluation, and standardization serving the fine ceramics industry of
Japan. The cost of its foundation was borne almost entirely by private
industry in the Chubu region. It appears that about half its current
annual operating budget of about $10 million (1 billion yen) now comes
from industry and the other half from government. The MT was told that
the current permanent staff is 72; in addition, there are 21 visitors
from industry who stay for about two years. It was noticed by the MT
that there are few middle-aged persons; most of the staff appears to be
very young (twenties and thirties) persons led by only a few senior
supervisors and directors. Two overview brochures (containing English.
* see below) were provided giving details on its history, Board of
Directors, organization, principal activities, equipment, and
facilities. The work appears to be aimed at both structural and
functional applications of ceramics; Hayakawa said that he expected the
work on functional applications to increase in the future while that on
structural to hold steady.
(* The MT noted that virtually every Japanese organization it visited
supplied English versions of high-quality, attractive (most in color),
up-to-date brochures or other information such as videos. That is
remarkable in view of the sizes of the organizations. In the US, such
high-quality information is usually supplied only by top-management or
major operating unit levels of many organizations, private or public.
Many of the Japanese organizations visited were no larger than typical
divisions, sections or groups of such US organizations. The MT
interpreted this as indication of genuine desire on the part of the
Japanese to communicate effectively.)
(There is no entity in the US comparable to the JFCC; the closest thing
would be a combination of the High Temperature Materials Laboratory at
the US Department of Energy's (DOE's) Oak Ridge National Laboratory
(ORNL) in Tennessee, which houses specialized test and characterization
equipment for use by US industry, and NIST, which does R&D on testing,
evaluation and standardization. The major differences are that the JFCC
does R&D related to development of specific commercial products while
the two US organizations do not, and that both US organizations are
essentially entirely government sponsored.)
The most notable development from JFCC seems to be a series of reference
samples of ceramic powders and sintered bodies. The ceramic powders
supplied are alumina (Al2O3), silicon nitride (Si3N4), silicon carbide
(SiC), boron nitride (BN), and barium titanate (BaTiO3). These are
primarily intended as standards for calibrating equipment and procedures
used to test or characterize other powders. The sintered bodies, on the
other hand, are intended as standards for calibrating strength and
toughness testing equipment and procedures and for comparisons of
ceramic machining equipment and procedures. Sintered bodies of alumina
and silicon nitride are currently available; zirconia (ZrO2) bodies will
be available soon.
The reference powders are supplied by Japanese manufacturers but are
characterized by JFCC. The reference sintered bodies are made by
Japanese firms (Al2O3 by Asahi, Si3N4 by NGK, and ZrO2 by
Toso...formerly Toyo Soda Manufacturing) from powders from other
Japanese suppliers following sintering procedures developed by JFCC. The
MT was given data and price sheets on both the reference powders and the
sintered bodies; the prices seem quite reasonable.
The MT was also shown a set of reference bodies used to detect slight
temperature variations in various parts of a high-temperature kiln or
furnace. These chicklet-shaped bodies become progressively more rounded
over time at a given temperature.
Thus, by placing these at various points in a furnace, one can visually
determine if there are temperature variations.
During the lab tour it was pointed out that their earlier work on
injection molding had been stopped and replaced by work on a new
national program aimed at developing nano-pore ceramic membranes for CO2
control and utilization. The MT was not shown ongoing work on ceramic
machining, ostensibly because of the associated dust and danger.
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National Industrial Research Institute of Nagoya (NIRIN):
NIRIN is one of six Japanese laboratories to bear the designation
"National Industrial Research Institute" (AIST also has nine more labs),
each located in different geographical regions of Japan. In 1993, these
six labs were told to begin focussing their attention on the main
interests of the regions in which they are located (and changed the
first word in their names from "Government" to "National"). Since the
Chubu region of Japan is heavily populated by industries interested in
production of materials, this institute has been told to concentrate its
research on materials, and ceramics in particular.
Dr. Yasuhiko Kondo, the new Director General, personally greeted the MT
and Mallard, showed a video overview of NIRIN, and presented three
packets of information (one in English) on the current research topics,
budget, and personnel. NIRIN was founded in 1952 by merging three
smaller institutes in the Chubu region. Dr. Kondo estimated that about
60% of the work at NIRIN is now on ceramics. Others in attendance
included Dr. Hideyo Tabata, Director of the Ceramic Science Department;
Dr. Makoto Kato, Director of the Materials Processing Department; and
two junior researchers, Dr. Koji Watari and Mr. Mamoru Mabuchi. The MT
had dinner the previous evening with Mr. Kazuo Kodaira, Head of the
Office of International Research Cooperation; his adviser, Dr. Susumu
Minato; and Watari, Mabuchi, and Takayanagi.
A major theme of the current ceramics work is on what they call
meso-scopic ceramics made by processing particles about 0.1 micrometers
in size, which imparts special properties such as superplasticity; NIRIN
was, in fact, where superplasticity in ceramics was first demonstrated
in the mid-1980s. Kondo indicated that NIRIN is currently working with
a Japanese automaker on superplastically formed piston rings. (It was
not clear whether the rings are metal or ceramic based.) This
meso-scopic ceramics research is apparently also part of the national
effort mentioned at JFCC (see above) on CO2 control and utilization.
Investigations into other aspects, such as how to control the flow of
such fine particles, are also underway.
Dr. Tabata mentioned that NIRIN has work underway aimed at avoiding or
minimizing machining damage, but gave no details. Work is also underway
on ways of purifying lower-grade, but lower-cost, silicon nitride so it
can be used to produce parts comparable to those made with top-grade,
but expensive, powders. NIRIN has a small branch at Seto with the
explicit mission of assisting the traditional ceramics industry in the
Chubu region, especially the small-to medium-sized firms.
-------------------------------------------------------------
Tokyo
National Research Institute for Metals (NRIM):
Though not directly connected to the purpose of the MT mission, a side
visit was made on June 8 with Dr. Yoshio Monma at the Tokyo laboratory
of the National Research Institute for Metals (NRIM) to discuss
collaborations between NIST and NRIM on inventorying various methods
used for determining and modelling certain lifetime properties of
ceramics. This pre-standardization effort would be a part of the
Versailles Project on Advanced Materials and Standards (VAMAS). The
Japanese under Monma are handling the inventorying of methods for metals
while the British are handling those for polymers. It was agreed that
initially NIST would work on inventorying methods for creep and stress
rupture. Later work would address fatigue, fracture toughness,
corrosion, and possibly wear, in that order of priority and as time and
funding permitted.
-------------------------------------------------------------
Tsukuba
On June 9, the MT took a day-trip from Tokyo to Tsukuba (the "Science
City") where it visited the National Institute of Materials and
Chemistry (NIMC), the National Institute of Research on Inorganic
Materials (NIRIM), and the Japan Automobile Research Institute (JARI).
Mallard of the DT accompanied the MT to NIMC.
National Institute of Materials and Chemistry (NIMC):
The MT and Mallard were greeted by the Director General, Dr. Jiro
Hiraishi, and then briefed on NIMC by Dr. Fusae Nakanishi of the
International Research Liaison Office. Dr. Nakanishi supplied three
data sheets outlining the current research, budgets and staff. NIMC is
an AIST lab formed in 1993 by the merger of all or parts of the National
Chemical Laboratory for Industry, the Industrial Products Research
Institute, and the Research Institute for Polymers and Textiles, three
smaller labs that were physically located side-by-side in Tsukuba. It
has a staff of about 345 with roughly one-third being from industry on
temporary assignment. The main focus of the lab is energy issues such
as alternate energy sources, pollution control, and environmentally
friendly industrial technologies.
Carpenter and Mallard then held discussions with Dr. Kikuko Hayamizu
regarding NIMC's Spectral Database System (SDBS). Mallard saw potential
for collaboration on a similar database at NIST. Dr. Kazutoshi Tanabe
and Dr. Tadafumi Uchimaru demonstrated a database search system for
identifying organic molecules containing given molecular substructures.
More detail is given in the DT report.
Pujari and Whalen of the MT visited Dr. Tetsuya Kameyama of the
Inorganic Reaction Control Lab for discussions of his work on the
synthesis of ultrafine (10 to 30 nm) ceramic powders via a RF plasma in
a dual-chamber apparatus; the RF plasma ensures that the particles are
crystalline as-synthesized (i.e., no additional annealing is needed).
The materials synthesized so far include SiC, WC1-x (a super-hard,
non-equilibrium phase), and FeSi2 (material used in catalysts). His
lab-scale rig can only produce 10 grams/hour, but he said that Sumitomo
Cement Company is scaling up the process for commercial production.
Another use for his plasma reactor is to put down calcium phosphate
coatings on ceramic materials intended for human implants. The calcium
phosphate aids in the bio-compatibility of the implant and improves the
potential for successful attachment of living tissue. The approach may
have potential for deposition of functionally graded coatings.
Another brief visit was made by Pujari and Whalen with Dr. Harumi
Yokokawa on his planar stack design for solid oxide fuel cells using a
porous layer interstack support system. This design is an alternative
to the Westinghouse tubular approach for power applications. This is
part of a larger national effort supported by the New Energy and
Industrial Technology Development Organization (NEDO). Yokokawa
described some of his work on identifying dopants for the lanthanum
chromite interconnect materials, but noted similar problems of long-term
stability that have plagued the fuel cell efforts in the US. Whalen
asked about the likelihood of continuing support from NEDO for this
work, to which question Dr. Yokokawa replied that it is part of a
"National Program," meaning that support was virtually assured until the
goals had been met.
-------------------------------------------------------------
National Institute for Research on Inorganic Materials (NIRIM):
The MT (Mallard stayed at NIMC) was given a brief overview by the Deputy
Director General, Dr. Yoshizo Inomata, and the Director of the
Administrative Division, Mr. Kenichi Takeyama, using an excellent
brochure (in English) giving details on its history, organization,
budget, staff, and current projects. NIRIM is a laboratory of the
Science and Technology Agency (STA) with the mission of conducting
fundamental research into advanced inorganic materials, which
essentially means ceramics since STA also has NRIM for metals research.
NIRIM is in the process of establishing itself as an international
Center of Excellence (COE) for ceramics, emphasizing microstructural
analyses of ceramics and studies of ceramics under high pressures and at
high temperatures. The COE has an international advisory committee
separate from the all-Japanese advisory committee for all of NIRIM.
NIRIM was founded in Tokyo in 1966 but was moved to Tsukuba in 1972 (the
first Japanese government research organization to move to Tsukuba). In
1994 it has a total permanent research staff of about 115 to 120 and an
operating budget of about $35 million (3.5 billion yen). In addition,
there are about thirty visiting Japanese scientists. The researchers
are organized into groups which focus on one type of ceramic for a
period of five years, after which the group is dissolved. In addition
to this specific-material-focussed research, the researchers may also
participate in inter-material projects that also are limited to five
years or so. For example, members of the Yttria Group, the Barium
Perovskite Group, and the Layered Lanthanum Oxide Group participate in
the Exploration of New Superconductors Project. In addition to Groups
and Projects, NIRIM also has three semi-permanent "centers" for
high-pressure, creation of new materials, and development of advanced
materials. NIRIM is most famous for its past research into silicon
nitride and diamond thin films.
After the initial briefing, the MT toured was briefed by Dr. Shinobu
Yamaoka at the High Pressure Research Lab and by Dr. Shigeo Horiuch at
1.5 million electron volt transmission electron microscope facility.
These were impressive facilities.
-------------------------------------------------------------
Japan Automobile Research Institute (JARI):
The MT met with Mr. Shoji Ishiwata, Director of the Ceramic Gas Turbine
(CGT) Division; Mr. Tsubura Nishiyama, Chief Leader of the CGT Project;
Mr. Arata Sumie, Supervisor; and Mr. Hiroshi Okano, Supervisor. The MT
was first shown a video and given two English brochures on JARI in
general, then a video and overhead presentations on the CGT effort in
particular. In addition, reprints of three recent papers detailing
progress in the CGT effort were given.
JARI is a private, non-profit organization set up in 1969 by the Japan
Automobile Manufacturers Association (JAMA) to conduct research of
common interest to the Japanese automotive industry. The size of the
permanent staff is on the order of 330, of which about 250 are
researchers. The total budget is on the order of $60-70 million per
year (6-7 billion yen). Officially, it is under MITI (but not under
AIST...ANRE, see below), but the breakdown of programs in FY 1992 given
to the MT indicates that most of the work is sponsored by Japanese
automotive companies and their suppliers, either individually or
collectively. Other, smaller sources of support are JAMA, contracts
from government sources other than MITI, and MITI. The CGT Program is
one of the latter, i.e., funded directly by MITI's Agency of Natural
Resources and Energy (ANRE) with supervision by the Petroleum Energy
Center. The MT was not given details as to the size of the CGT Program
in funding or personnel.
The CGT Program is a seven-year effort begun in June 1990. Its aim is
to demonstrate a prototype of a 100 kW (approximately 135 hp) automotive
engine containing substantial ceramic components in the combustion train
and surviving at least 100 hours at maximum rated capacity. (It is
comparable to similar programs underway in the US under Department of
Energy sponsorship.) Toyota, Nissan, and Mitsubishi are the main
automobile manufacturers involved and NTK, NGK, and Kyocera are the main
ceramic suppliers participating. The four supervisors the MT met were,
in fact, detailees from the automotive companies, and expect to return
to their firms when the CGT Program is over.
The four researchers indicated that as of the end of the fourth year
(June 1994), the program has successfully completed tests of separate
components. Non-rotating (static) components survived more than 100
hours at 1200 C, but rotating parts only survived a bit more than 25
hours. The failure is thought to result from fatigue induced by
high-frequency vibrations occurring during resonances during run-up or
run-down. They will try redesigning the components so as to minimize
the peak stresses during the resonances and/or modify the engine test
cycle so as to go through the resonances quickly or force the resonances
to occur at lower temperatures where the materials are a bit stronger.
Still, the JARI researchers felt that these approaches will only be
stopgap answers and that material solutions will have to be found
somehow for commercial applications to be viable. Pujari and Whalen
noted that this same problem has been observed in the US programs.
Ultrasonics and shock-wave testing were discussed as possible ways of
inducing such high-frequency vibrations without actual spin-testing. An
interesting study might be to determine whether the burst stress of a
component by shock-wave testing correlates to the fracture strength
measured by standard laboratory tests such as modulus of rupture (MOR)
bar tests. Whalen contended that there is little or no correlation
between the burst stress in a spin-test and the MOR bar fracture
strength, and suggested that investigation of why this is so might be
useful. Whalen and Pujari asked if there might be any interest in
trying their respective firms' (viz., St. Gobain/Norton's and
AlliedSignal's) materials in the tests. The JARI researchers indicated
that there would be interest in such new materials, but only in the long
term since their current CGT Program has only three years left. They
feel that they must stick with the materials they have now in order to
meet their deadline.
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Sendai (Tohoku)
On Monday, June 13, the MT visited the Kakuda Research Center of the
National Aerospace Laboratory (KRC/NAL) and the Tohoku National
Industrial Research Institute (TNIRI). On Tuesday, June 14, the MT
visited the Institute of Materials Research of the Tohoku University
(IMR/Tohoku). On the evening of June 13, the MT had dinner with
personnel from KRC/NAL, IMR/Tohoku, and Nippon Steel Corp. The
principal point of discussion at these three places was functionally
graded materials (FGMs).
Kakuda Research Center of the National Aerospace Laboratory (KRC/NAL):
The MT was transported from its hotel in Sendai to the KRC/NAL facility
in Kakuda (about an hour from Sendai by car or train) by Dr. Masanobu
Niino.
The first stop was a meeting with Mr. Hiroshi Miyajima, the
Director-General of KRC/NAL, who provided an overview of all of NAL,
including a very good brochure in English. NAL is the STA organization
concerned with aeronautic and aerospace research, development, and
testing. The work appears to be shaded toward fundamental or
early-stage work, i.e., technology base; the actual flight testing of
major systems is done by the National Space Development Agency (NASDA).
NAL's main facility is in Chofu, near Tokyo; the KRC facility in Kakuda
is primarily concerned with propulsion; it is basically an engine
testing facility. Current emphases are on rockets for a Space
Shuttle-like vehicle and supersonic ramjets (or "scramjets") for a
"spaceplane," i.e., an airplane-like vehicle capable of taking off and
landing like a conventional airplane but also of going into low orbit on
its own without booster rockets. (The comparable US concept is called
the National Aerospace Plane, or NASP.) KRC's closest US analogue is
the Lewis Research Center (near Cleveland, OH) of the National
Aeronautics and Space Administration (NASA).
FGM is essentially the only materials-related work at KRC/NAL; there is
other materials-related work at the Chofu NAL facility. FGM SiC on
carbon reinforced/carbon matrix (C/C) composites are used in the rocket
nozzles of Japan's new LE-7 hydrogen-fueled rocket engine. It was noted
that ceramic seals were not selected for the LE-7 simply because they
were felt not to be as ready for use in rocket engines as are polymer
seals. Mr. Miyajima indicated that, since Japan has no large
aeronautical or aerospace industry to speak of, the goal of the Japanese
government's efforts in aerospace technology is primarily so Japan can
be a credible contributor and participant in future international space
efforts. It was noted that a Japanese has already flown on a Russian
space mission.
Detailed discussions were then held on FGMs with Dr. Niino, Mr. Y.
Wakamatsu, Mr. Y. Kuroda, Mr. Akinaga Kumakawa, and Dr. Lidong Chen.
Dr. Wakamatsu told the MT that the initial FGM work had been conducted
from 1987 through 1991 and was mainly on zirconia-on- copper FGMs for
the rocket nozzles of the LE-7. The FGM developed is called the Thermal
Stress Relaxation Type. That initial work involved FGM layer design,
production (by others) of FGM samples, and evaluations of the samples
for their thermal protection capabilities by KRC/NAL using its special
high-temperature gradient apparatus described below. This effort was
led by Dr. Niino; Wakamatsu, Kuroda, and Kumakawa were responsible for
the thermal evaluations of the samples; and a Mr. Moro was responsible
for building a database of properties of the FGMs tested. Outside
organizations included the Chofu NAL facility, the Mechanical
Engineering Laboratory in Tsukuba, NRIM, Nippon Steel, NKK, and Nippon
Oil.
In 1992 the effort was focussed toward more thorough development of
SiC-on-C/C and zirconia (ZrO2)-on-metal FGMs for use in liquid rocket
combustors, thermal protection systems (TPSs) of the spaceplane, and in
the scramjet. The main outside organizations are Tohoku University,
Mitsubishi Heavy Industries, Kawasaki Heavy Industries, Nippon Steel,
and Nippon Oil. The financial support for this is from NAL. In
addition, NASDA is supporting a feasibility study of ZrO2, SiC, C, TiC,
and TiB2 FGMs for future TPS of the spaceplane. This feasibility study
is being coordinated for NASDA by the Society of Non-Traditional
Technologies.
Dr. Niino then described their newest program called HYDECS aimed at
producing FGM "stacks" of thermionic and thermoelectric materials
capable of 40% efficiency of conversion of heat to electricity. The
stack will be a succession of layers, each selected for its optimal
conversion efficiency at the temperature range seen in the layer
sequence from the hot side to the cold side. The materials in sequence
from hot side to cold side will be bismuth telluride (Bi2Te3), lead
telluride (PbTe), Si.7Ge.3, and lanthanum telluride (LaTe1.4). The heat
source will be either solar or nuclear up to 1400K. Niino indicated
that the envisioned application is a "lunar energy park" in which
thermal energy from solar collectors and nuclear reactors on the moon
will be converted to electrical energy, then to laser energy, and beamed
back to earth via Earth-orbiting satellites. The program is funded by
STA at about $15 to $20 million (1.5 to 2 billion yen). Phase I began
in April 1993 and runs through March 1996; Phase II will begin in April
1996 and run through March 1998. Forty organizations and about 100
persons are involved. The work of Phase I is divided into materials
synthesis, design, evaluation, processing, and databases. There will be
a Japan-Russia Workshop on Thermoelectrics and Thermionics in Sendai
January 24-26, 1995.
The MT was given a tour of some of the KRC/NAL facilities and inspected
some equipment pertinent to FGM technology. The High-Temperature
Gradient Device is a two-story device in which 1-3 MW from an arc lamp
can be focussed to a spot 1 mm^2 on a specimen, the back of which is
cooled by liquid nitrogen. A steady surface temperature and temperature
gradient are established, the final steady-state surface temperature
depending mainly on the thermal conductivity of the FGM, the higher the
conductivity the lower the surface temperature. Mr. Kumakawa noted that
the surface temperatures of many specimens change with time and repeated
heatings, and speculated that microcracking may be the cause.
Other test rigs included a hot gas flow test device in which 100 mm^2
specimens can be exposed to temperatures up to 2900K and a small gas
burner test device in which specimens 30 mm in diameter can be exposed
to temperatures up to 3000K. The MT also saw small bipropellant
thruster rockets which utilize FGMs for thermal protection.
-------------------------------------------------------------
Tohoku National Industrial Research Institute (TNIRI):
TNIRI is the AIST NIRI serving the Tohoku region (the northern-most
prefectures of the main island of Japan). (Note, however, that this
NIRI uses the acronym TNIRI whereas the one in Nagoya - see above - uses
NIRIN.)
The MT held discussions with Dr. Jun Ikeuchi, Director of the Division
of Materials Engineering, and Mr. Nobuhiro Sata and Dr. Hitoshi
Hashimoto, both senior researchers in the same Division. Mr. Sata also
has a second position of Deputy Officer of Research Planning for all of
TNIRI. The MT was shown a video and given a brochure and a recent
newsletter detailing its history, organization, budget, personnel and
main research thrusts. It was formed in 1967-68 as a Government
Industrial Research Institute from predecessors dating back to 1928.
Its name change to TNIRI occurred in January 1993. It is relatively
small with a staff of only 53 of which about 30 are researchers and a
budget of about $30 million (3 billion yen). It has only two research
divisions, Materials Engineering and Molecular Chemistry, and there does
not seem to be major focus areas, the possible exceptions being
geothermal and biological which are of specific concern to the Tohoku
region. Ikuechi indicated that the institution is in the process of
focussing its attention more toward materials, especially metals.
Composites (mostly polymeric matrix) have been an area of special
attention in the past.
Hashimoto then discussed his work on mechanical alloying of metals and
Sata discussed his work on self-propagating high-temperature synthesis
(SHS). Sata noted that his thirteen years of SHS work was coming to a
close and that he was planning to move on to work in the area of
intelligent materials. In the course of his past work, he had prepared
FGM samples via SHS for test by KRC/NAL, but that was just about all
that TNIRI has done in the FGM area. Ikeuchi indicated that TNIRI did
have ultrasonics capabilities, but only to about 25 MHz which would be
too low for FGM characterization.
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Institute for Materials Research of the Tohoku University (IMR/Tohoku):
The IMR/Tohoku is an independent research organization affiliated with
the Tohoku University in Sendai. It was founded in 1916 and until 1987
was known as the Research Institute for Iron, Steel and Other Metals.
The principal interest of the MT was in seeing Dr. Toshio Hirai and
colleagues who have been interested in FGMs and who have collaborated
extensively with Niino and colleagues at KRC/NAL.
Dr. Hirai first gave the MT an overview of IMR/Tohoku in general and his
research group in particular. He provided a 1993 brochure on IMR/Tohoku
which identified his group as officially the High-Temperature Materials
Science Laboratory of the Materials Development Division, one of four
such divisions of IMR/Tohoku. IMR/Tohoku has about 330 permanent staff
members and a budget of about $40-50 million (4-5 billion yen). The bulk
of the funding comes from the Ministry of Education, Science and Culture
(MONBUSHU), the rest from other government agencies and private
industry. The exact nature of the relationship with Tohoku University
was not made clear; conversation at dinner on June 13 indicated to the
MT that IMR/Tohoku staff members officially bear titles as members of
the faculty of the university but, in fact, most do not teach courses.
Tohoku University students, however, conduct research at IMR.
Hirai also gave the MT a list of the current (as of April 1994)
personnel and projects in his laboratory. The projects are grouped into
seven topics: chemical vapor deposition (CVD), nanocomposites,
sintering, superconduction, FGM, plasma processing, and solid state
ionics. Despite the names of his lab and of these groups, the main
focus is chemical vapor deposition (CVD), especially on ways of
increasing the rate of CVD and depositing nanocomposited coatings. The
laboratory was established in 1974 mostly to investigate CVD of
non-oxides for structural purposes. Dr. Hirai noted, however, that the
old emphasis on non-oxides was decreasing mostly due to increasing
concerns about the hazards of materials used in producing non-oxide CVD
deposits. He said that the laboratory tends to concentrate more on
investigating new ways of synthesizing CVD deposits and less on
characterizing them. The MT noted that the characterization mostly
consisted of x-ray diffraction analysis, scanning electron microscopy,
and differential scanning calorimetry.
The MT toured Hirai's labs with Dr. Mamoru Omori, Dr. An-Pang Tsai, Dr.
Hiroshi Matsumoto, and Dr. Takashi Goto. Dr. Omori showed the labs
where much work on rapidly solidified amorphous metals has been done.
Omori also showed a device in which a spark-induced plasma is used to
scour powder particles in order to enhance their sinterability during
subsequent, standard heating. This approach has been used to produce a
variety of FGMs, including zirconia on stainless steel and aluminum on
polyimide. The present plasma system is rated at only 5 volts, but a
new one will be capable of 200 volts. Tsai's lab deals with attempts to
produce semi-amorphous and quasi-crystalline materials and process them
into bulk materials. Some FGM work is done via sputtering and laser
ablation. Matsumoto showed his electron cyclotron resonance coater
which uses a microwave field at 2.45 GHz to produce activated deposition
onto substrates at temperatures lower than those usually required for
non-activated CVD. Goto showed work on CVD of Ir, Pt or Si onto ZrO2
for applications in water decomposition devices. He is also doing work
on preparation of B4C-SiC eutectics by arc-melting in Ar.
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ACKNOWLEDGEMENTS
The MT members recognize and thank for their good work in arranging and
guiding the visits: Dr. Phyllis Genther Yoshida and Ms. Patti
O'Neill-Brown of Dr. Good's Washington staff and Mr. Robert Kuntz and
Ms. Elizabeth Nelson of the US Embassy in Tokyo. MT Leader Carpenter
thanks Dr. David Kahaner of NIST, currently at the Office of Naval
Research - Asia in Tokyo, for assistance in identifying the Japanese
organizations to be visited during this trip.
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PROFILES OF MATERIALS TEAM MEMBERS
Joseph A. Carpenter, Jr. is a General Physical Scientist in the Ceramics
Division of NIST, Gaithersburg, MD. His main duties are technical
assessments and planning for multi-disciplinary projects at NIST
involving materials. He holds a B.S. in Metallurgical Engineering and a
Ph.D. in Materials Science and Engineering from the Virginia Polytechnic
Institute and State University. His previous positions were at the
Chrysler Corporation and the Oak Ridge National Laboratory (ORNL). At
ORNL he first did development work on ceramic nuclear fuels and then
became technical manager of a national DOE program involving R&D on
materials for energy conservation. He has been at NIST for over six
years, where he has been involved in materials for electronic and
photonics and in materials aspects of international standards.
Vimal K. Pujari is a Senior Research Associate at Saint-Gobain/ Norton
Industrial Ceramics Corporation, Northboro, MA. He received a B.Sc. and
M.Sc. in Engineering from the Banares Hindu University, India, and the
Ph.D in Mechanical Engineering from the University of California at
Berkeley. Previous jobs have been with the Corning Glass Works, the
Bendix Corporation, and Martin Marietta Laboratories. He has had
experience with near net shaping of monolithic and composited ceramics,
ceramic powder handling, and design and testing of structural ceramics
for high-temperature applications. He was the principal investigator
and technical manager for a major program funded by the US Department of
Energy on ceramics for automotive applications.
Phillip J. Whalen is a senior member of the Ceramic Materials Skill Base
at the central research facility of AlliedSignal, Inc. in Morristown,
NJ. He received the B.S., M.S., and Ph.D. degrees in Ceramic Science
and Engineering from Rutgers University. Since joining AlliedSignal
from Rutgers he has worked in a number of areas dealing with the
processing and characterization of structural ceramics for aerospace,
automotive and other engineering applications. The relationships
between mechanical performance and process defects have been central to
his work. He has worked on yttria-zirconia, silicon nitride, silicon
nitride/silicon carbide composites, and single crystal oxides. He was a
participant in the development of GS44, a high-strength,
high-fracture-toughness silicon nitride presently being produced by
AlliedSignal.
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