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previous paper (Ref 32), single crystal
superalloys and oxide dispersed super-
alloys are being studied. The advance-
ments in Japan over the past 2 years in
superalloy development have not been
substantial. Superalloys equivalent to
CMSX 4 and PWA 1484 are available
and more advanced systems are being
developed, but the emphasis seems less
than it had been previously. Horibe at
NRIM (Tokyo) is performing research
on crack propagation in ceramics such CONCLUDING REMARKS
as SiC. Iguchi at Tohoku University is
doing some very good research con-
cerned with extractive metallurgy pro-
cesses. There is a sizeable research effort
in Japan on materials to be used in
nuclear reactors and radiation damage
effects. For example, very elegant TEM
studies on defects induced in ceramics
by radiation are being performed at
the Tokyo Institute of Technology where
resolutions of about 3 Å have been
achieved.

has been established. This center is
directed at developing advanced mate-
rials, advanced devices, and advanced
systems. At the National Aerospace
Laboratory an extremely well equipped
materials test laboratory has been
completed. A number (Ref 7) of the
completed. A number (Ref 7) of the
latest model Instron testing machines
with environmental controls, and
computer operated, are available.

It is also important to emphasize that research facilities throughout Japan are being upgraded and expanded. As an example, Nippon Steel has just completed its new research and engineering laboratory. It is in Futtsu City, which is about a 1-hour train ride from Tokyo. It will be Japan's largest privatesector research laboratory. A staff of about 1,200 will be employed: 400 researchers, 400 research assistants, and 400 engineers. Equipment is beginning

to be installed and some research is already in progress. It is truly a very impressive facility and unquestionably will be responsible for significant technical breakthroughs in the future. This center will not only be involved with steel research, development, and engineering but also new materials and new technologies. While the Nippon Steel Research and Engineering Center is the most notable example of the emphasis that is placed upon materials research, numerous other examples are evident. At Tokyo University a Research Center for Advanced Science and Technology

During a 1-year stay in Japan 2 years
ago, this author concluded that mate-
rials research in Japan was important,
but that almost all of the research was
direct-application oriented. Moreover,
most often the research was on topics
initially discovered in other countries.
During the present visit, signs are evi-
dent that such views will not be accu-
rate in 5 to 10 years. More research is
being done to determine mechanisms
and because it is interesting. The com-
mitment to long term research is evi-
dent. There is, and will be, good research
in many countries throughout the world
that certainly will be as good as or, in
some cases, better than that in Japan.
However, there should not be any
question that important materials
research accomplishments will be
achieved in Japan. At the present time
research on Nb,Al is being emphasized
in Japan, while the effort has been

curtailed in the United States because
the problems of oxidation are too severe
for applications where part failures
would cause catastrophic effects. It will
be interesting to see how this research
in Japan on Nb,Al progresses.

REFERENCES

1. M. Yamaguchi, "Overview-Japan
with particular emphasis on TiAl,” in
Proceedings of the International Confer-
ence on High Temperature Intermetal-
lics, 30 April-2 May 1991 (The Royal
Society, London), 15-29.

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11. Y. Mishima, S. Miura, and T. Suzuki, Bulletin of the Japan Inst. Metals 30, 6 (1991).

22. K. Ito, H. Inui, and M. Yamaguchi, 30. M. Sayashi, K. Maki, T. Noda, and
to be published.
S. Isobe, Proc. 1990 Sendai Meeting
(Japan Inst. Metals, Sendai, 1990),
p. 277.

23. T. Hirai and M. Sasaki, JSME Inter

12. T. Hirano, Acta Metall. Mater. 38, national Journal 34, 123 (1991). 909 (1990).

13. T. Hirano, S.-S. Chung, Y. Mishima, and T. Suzuki, “Improvement of room temperature ductility of Ni,Al by unidirectional solidification," in MRS Symposium Proceedings 213, 635 (1991).

24. M. Sasaki and T. Hirai, “Fabrication and thermal barrier characteristics of CVD SiC/C functionally gradient material," in Proceedings of the First International Symposium on FGM, M. Yamanouchi, M. Koizumi, T. Hirai, and I. Shiota, editors (Sendai, 1990),

14. T. Hirano, Scripta Met. 25, (1991). p. 83.

15. T. Hirano and T. Kainuma, ISIJ 25. M. Taki, Y. Fujisawa, Y. Sofue, International, in press.

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and T. Yoshida, "A fundamental study on the application of FGM to hightemperature rotating members," in Proceedings of the First International Symposium on FGM, M. Yamanouchi, M. Koizumi, T. Hirai, and I. Shiota, editors (Sendai, 1990), p. 353.

26. T. Hirai and M. Sasaki, "In situ processing of inorganic composites by chemical vapor deposition," in Advanced Structural Inorganic Composites, P. Vincinzini, editor (Elsevier Science Publishers B.V., 1991), p. 541.

31. M. Yoshihara and R. Tanaka, Bulletin of the Japan Inst. Metals 30, 61 (1991).

32. F.S. Pettit and E.M. Lenoe, "High temperature materials research and development in Japan,” Scientific Information Bulletin 14(2), 43-97 (1989).

33. A. Takei and A. Ishida, "Aluminized coatings on titanium alloys and TiAl intermetallic compound," in Proceedings of the International Symposium on solid State Chemistry of Advanced Materials, Part B, Workshop on High Temperature Corrosion of Advanced Materials and Protective Coatings, 5-7 December 1990, Tokyo, Japan, in press.

34. T. Narushima, T. Goto, and T. Hirai, J. Amer. Ceram. Soc. 72, 1386 (1989).

35. T. Narushima, T. Goto, Y. Iguchi, and T. Hirai, J. Amer. Ceram. Soc. 73, 3580 (1990).

27. T. Hirai and T. Goto, Bull. Jpn. 36. T. Narushima, T. Goto, Y. Iguchi,
Inst. Met. 28, 960 (1989).
and T. Hirai, "High-temperature active
oxidation of CVD-SiC in Ar-O, atmo-
sphere," accepted for publication in
J. Amer. Ceram. Soc.

28. Y. Shida and H. Anada, “Effect of ternary alloying elements on the oxidation behavior of Ti-Al intermetallic compounds," in Proceedings of the International Symposium on Solid State Chemistry of Advanced Materials, Part B, Workshop on High Temperature Corrosion of Advanced Materials and Protective Coatings, 5-7 December 1990, Tokyo, Japan, in press.

29. K. Kasahara, K. Hashimoto, H. Doi, and T. Tsujimoto, J. Japan Inst. Metals 54,948 (1990).

37. J. Narushima, T. Goto, Y. Iguchi, and T. Hirai, "High temperature oxidation of CVD-SiC in CO-CO, atmospheres," in Proceedings of the International Symposium on Solid State Chemistry of Advanced Materials, Part B, Workshop on High Temperature Corrosion of Advanced Materials and Protective Coatings, 5-7 December 1990, Tokyo, Japan, in press.

38. K. Ohmura, M. Yamanoka, M. Fukaya, and H. Abo, "Effect of lanthanoid on oxidation behavior of Fe-Cr-Al foil," in Proceedings of the International Symposium on Solid State Chemistry of Advanced Materials, Part B, Workshop on High Temperature Corrosion of Advanced Materials and Protective Coatings, 5-7 December 1990, Tokyo, Japan, in press.

39. S. Kihara, A. Otomo, I. Kajigaya, and F. Kishimoto, Werkstoffe and Korrosion 39, 69 (1988).

40. S. Kihara, K. Nakagawa, and W. Wolowoduk, "Corrosion resistance of advanced tube materials in coal-fired boiler," in Proceedings of the International Symposium on Solid State Chemistry of Advanced Materials, Part B, Workshop on High Temperature Corrosion of Advanced Materials and Protective Coatings, 5-7 December 1990, Tokyo, Japan, in press.

F.S. Pettit is a William Kepler Whiteford Professor in the Department of Materials Science and Engineering at the University of Pittsburgh. He was a liaison scientist with the Office of Naval Research Asian Office from June 1988 through August 1989 while on sabbatical from the university. Dr. Pettit's professional interests are in high temperature materials and surface stability and the use of coatings for protection.

UNITED STATES-JAPAN COOPERATIVE PROGRAM IN NATURAL RESOURCES (UJNR)

A new subdivision of the United States-Japan Cooperative Program in Natural
Resources, Deep Marine Technology, met for the first time in Hakone, Japan.
Technical advances and announcements of innovative programs by the
Japanese and future research plans by the Americans highlighted the meeting.
Brief reviews of papers in the four topical areas (biology, observation platforms,
geology, and programmatic research) are presented.

INTRODUCTION

by Pat Wilde

be conducted from a submersible,
ROV (remotely operated vehicle), AUV
(autonomous underwater vehicle), or
towed system in the Pacific Ocean in
the next 5-10 years." This article reports
on the sessions of the Deep-Sea Science
Group.

The United States-Japan Coopera-
tive Program in Natural Resources
(UJNR) was established in 1964. The
UJNR program of science and tech-
nology interchanges now has 16 panels
of which Diving Physiology and Tech-
nology is one of the most successful
and longest running. The major focus
of the panel, generally called the Div-
ing Panel, is diving physiology and atten-
dant submersible research. The Japanese
coordination is through the Japan
Marine Science and Technology Cen- BIOLOGICAL REPORTS
ter (JAMSTEC), while the United States
effort is through the National Oceanic
and Atmospheric Administration
(NOAA) of the Department of Com-
merce. Formal exchanges between scien-
tists are held every 2 years, generally
alternating between countries. An
innovation was introduced to the Div-
ing Panel meeting this year at Hakone,
Japan, with the operation of two simul-
taneous research sessions. The major
session continued to focus on diving
physiology as the "Hyperbaric Group,"
but recognizing that technology was
advancing in the submersible field, a
second session was added on deep
marine technology as the "Deep-Sea
Science Group." The focus of this new
session was "deep-sea research that can

The new group attracted 22 speakers, 13 from the United States and 9 from Japan. The sessions were co-chaired by Dr. Hiroshi Hotta of JAMSTEC and Dr. Sylvia Earle, chief scientist of NOAA.

The initial talks were on biology. Dr. Chiaki Kato, JAMSTEC, discussed deep-sea microbiological research at JAMSTEC, describing the DEEPSTAR (Deep-sea Environment Exploration Program Submarine Terrain Animalcule Retriever) initiative, which will move into a 6-story, 6,000-m2 new facility at JAMSTEC in 1993. This paper was coauthored by Dr. Koki Horikoshi. Dr. Kato also described the development of an isolation chamber and collection system as well as a sterilized mud sampler for the SHINKAI 6500 submersible.

Dr. Laurence Madin of Woods Hole talked on the use of submersibles for research on deepwater zooplankton and nekton, limiting his discussion to

intermediate midwaters of 1,000 meters or less. U.S. research focuses on taxonomy of organisms, behavior, bioluminescence, benthopelagic organisms, and detritus as marine snow. He noted that a major source of marine snow was from gelatinous mucous of appendicularians where the actual animal was much smaller than its contribution to the organic detritus. There is interest in the biology of deeper waters, but at present access to submersibles and appropriate technology limits the realistic expectation to investigations in midwaters.

Dr. Tetsuo Hamamoto of the DEEPSTAR group at the Riken Institute reported on work with his colleague, Dr. Koki Horikoshi, on characterization of an amylase from a psychrotrophic Vibrio isolated from a deep-sea mud sample. He stressed the value of the studies of extremophiles as they are found surviving at both high and low pH (<3, >9), temperatures (<10 °C, >70 °C), high salinity (>150 ppt), in the presence of >1% organic solvents, high concentrations of heavy metals such as Hg and Cd and sulfides, and at great pressure. He sees the potential application of such organisms as insights in the design of biocatalyzers for high temperature and pressure industrial processes.

Dr. W. Waldo Wakefield of the National Marine Fisheries Service of NOAA talked on the general topic of the application of marine technology to research needs in deep-sea biology for the coming decade. He used as an example studies of the carbon requirements of the benthic boundary layer which combine examination of the passive rain of carbon samples by sediment traps to respiration studies both of nekton and infaunas in chambers or by electrodes. He noted that the flux is just not that of simple rain of detrital carbon from above but involves animal migration via eggs and larva to along bottom down slope flows. As expected, the in-situ metabolic studies show that the carbon demand from the sediment community far exceeds that of the free swimming organisms. However, carbon budgets show high temporal and spatial variability with a real time mismatch of supply and demand with the apparent paradox that demand exceeds measured supply. He also described the remote vehicle used in such studies of sedimentary metabolism developed by Dr. Smith and Dr. Rymers of Scripps.

Dr. Takashi Okutani of Tokyo University gave a paper titled "Marine Biological Wealth Brought by Submersibles--New Light to Molluscan Systematics as an Example," coauthored by Dr. Katsunori Fujikura and Dr. Jun Hashimoto, both of JAMSTEC. Dr. Okutani reported on the value of the use of submersibles in the discovery of new communities, especially those of vents where the bathymetry is usually too rough that prior researchers didn't bother to dredge them. Some of the snails found close to hot vents apparently have symbiotic sulfur bacteria. Accordingly, he suggests that "molluscan systematics as well as physico-ecology of deep-sea animals" will have to be revised in light of the discoveries made possible by submersibles.

Dr. David Stein of the National Undersea Research Program (NURP) of NOAA presented "Deep Nekton: Prospects for Future Studies Using Undersea Vehicles." He stressed the need for in-situ trap studies, which only can be done by submersibles. Dr. Stein posed the problem of illumination in the deep sea. It is required for humans to see and to manipulate samplers. But light is not the natural environment in the deep sea, so how valid are the census measurements and even the behavioral studies done in visible light? Could it be that the old midwater trawl census data are more valid than those taken by submersibles or by cameras using visible light? He suggested investigation of other sources of illumination to provide a more natural sampling environment. Also, Dr. Stein indicated a need for a study on the avoidance of nekton of submersibles. Due to the lack of data and the large area of the deep ocean, he supported more use of unmanned vehicles, which are much cheaper and safer to operate than manned submersibles.

Dr. Sylvia Earle of NOAA talked on the results of the SHINKAI 6500 dive and deep-sea science and technology needs. Dr. Earle was fortunate to be one of the first Americans to dive in the SHINKAI 6500 (depth of 6,500 meters), the deepest diving research submersible. As noted above by Dr. Stein, the problem of the influence and impact of artificial light on natural populations accustomed to total darkness or at most bioluminescence is a nagging one. Dr. Earle proposed using the Army's night vision infrared goggles, which detect only ambient light. The experiment was done with red filtered light with bated fish attractants. Accordingly the submersible was essentially invisible to the biota. She reported on such phenomenon as bioluminescent ink from squid, commenting that 13 phyla demonstrate bioluminescence.

SEAFLOOR OBSERVATIONS AND OBSERVATORIES

Dr. Yoshio Ueda of the Japanese Hydrographic Department, representing his colleagues Drs. Akira Asada, Fusakiti Ono, Yoshio Kubo, and Motoji Kawanabe, reported on the ROV MARCAS 2500's survey work in Sagami Bay to select a site for a seabottom observatory to observe crustal movements. In conjunction with the survey, tests were run on horizontal distance and vertical displacement devices. The goal was to resolve centimeters over a distance of 1 km. Of the various signal sources tried, chirping at between 30 and 50 kHz gave the best results. The vertical meter uses a pressure sensor with a target resolution of 1 cm.

Dr. Makoto Yuasa of the Geological Survey of Japan, in his paper titled "Submarine Pumice Volcano A Submersible Study," has proposed that Myojin Knoll in the Izu-Ogasawara (Bonin) Arc may be a new type of acidic pumice submarine caldera, which is characterized by a high gravity anomaly but a weak magnetic anomaly. Submersible studies show that the knoll is constructed of layers of stratified pumice and dacitic lava that provide the framework for the volcano.

Dr. John Lupton of the University of California, Santa Barbara reviewed research needs for in-situ sampling and data collection at submarine hot springs and cold seeps. Dr. Lupton also discussed the U.S. RIDGE program and its various international and national counterparts as an example of an integrated research program involving many institutions but focusing on a geologically specific topic. One of the characteristic features of the oceanic ridgerise system is the vents which, because of their small size, transitory nature, and sometimes hostile environmental conditions, require specialized and demanding sampling devices and

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