Radiation Effects Review Meeting

345 Pages·1956·24.82 MB·English

-?--
%3
4
i
TID-7515(PtO 2)(De10) 7
1
2
RADIATION EFFECTS ON MATERIALS 1I
1
UNITED STATES ATOMIC ENERGY COMMISSION
1
PAPERS PREPARED FOR RADIATION
EFFECTS REVIEW MEETING, CONGRESS
HOTEL, CHICAGO, JULY 31-AUGUST I,1 956
August 1.956
Division of Reactor Development
1
Washington, D. C. '>
Technical Information Service Extension, Oak Ridge, Tenn.
-
i
-
i,
DISCLAIMER

This report was prepared as an account of work sponsored by an
agency of the United States Government. Neither the United States
Government nor any agency Thereof, nor any of their employees,
makes any warranty, express or implied, or assumes any legal
liability or responsibility for the accuracy, completeness, or
usefulness of any information, apparatus, product, or process
disclosed, or represents that its use would not infringe privately
owned rights. Reference herein to any specific commercial product,
process, or service by trade name, trademark, manufacturer, or
otherwise does not necessarily constitute or imply its endorsement,
recommendation, or favoring by the United States Government or any
agency thereof. The views and opinions of authors expressed herein
do not necessarily state or reflect those of the United States
Government or any agency thereof.
DISCLAIMER

Portions of this document may be illegible in
electronic image products. Images are produced
from the best available original document.
Date Declassified: June 13, 1958.
LEGAL NOTICE
This report was prepared as an account of Government sponsomd work. Neither the
United States, nor the Commission, nor any person acting on behalf of the Commission:
A. Makes any warranty or representation, express or implied, with respect to the ac-
curacy, completeness, or usefulness of the information contained in this report, or that the
use of any information, apparatus, method, od process disclosed in this report moy not in-
fringe privately owned rights) or
8. Assumes any liabilities with respect to the use of, or for damages resulting from the
use of any information, apparatus, method, or process disclosed in this report.
As used In the above, "penon acting on behalf of the Commission" includes any em-
ployee or contractor of the Commission to the extent that such employee or contractor
prepares, handles or distrlbutes, or provides access to, any information punuant to his em-
ployment or contract with the Commission.
This report has been reproduced directly from the best
available copy.
Issuance of this document doee not constitute authority
for declassification of classified material of the same or
similar content and title by the same authors.
Printed in USA. Price $5.00. Available from the Office
of Technical Services, Department of Commerce, Washington 25,
D. C.
AEC Technical Information Service Extension
Oak Rldge. Tennessee
---
-. e-- _I e -. _, -__- "
3
TABLE OF CONTENTS
Page
A Brief Summ~lryO f Research On Radiation Effects In Solids.
By Members Of Solid State Division. Oak Ridge National
Laboratory, Oak Ridge, Tennessee.....,........................... 5
Radiation Effects On Moderator, Shielding and Structural
Materials. By Milton Le.w..i.s.. ..G..e.n.e.r.a.l. .E.l.e.c.t.r.i.c. .C.o.m..p.an.y.,. .........
Richland, Washi~ton... 101
Evaluation Of U-Mg Matrix Fuel Material. By Maxwell D. ......
Freshley. General Electric Company, Richland, Washington.. 156
-
Radiation Effects On Reactor Materials A Review Of KAPL
Work. By J. F. Eckel, C. A. Bruch., A. Levy, A. H. W i l l i s , and
W. E. Seymour. Knolls Atomic Power Laboratory, Schenectady,
New York.......................................~o.....e~..s.o.... 170
Review Of Radiation-Effects Programs At Battelle. By H. A.
Saller, R. W. Dayton, and G. D. Calkins. Battelle Memorial
Institute, Columbus, Ohio........................................ 222
Effect Of Radiation On The Rate Of Oxidation Of Graphite.
By. W. L. Rosiba and D. H. Gu.r.in..s.k.y... ...B.r.o.o..k.h.a.v..e.n. .N.a..t.io..n.a.l. ...
Laboratory, Upton, New Pork.. 231
ANL Reactor Materials Irradiation Program. By S. H. Paine and
J. H. Kittel. Argonne National Uboratory, Lemont, Illinois..... 249
Summary of Bettis Irradiation Data On Reactor Fuel, Structural,
And Control Rod Materials. By R... .H... .F.i.l.ln.o..w... ..B..e.t.ti.s. .P.l.a.n.t.,. .....
Pittsburgh, Pennsylv8rTlia....... 268
-. - . - ._ _ ~ ..x.. _ ._. -. .............. - ....
4
TABLE OF CONTEIWS (Continued)
Radiation Results Of Screening Tests On Fuel Alloys For the
APIA Fast Breeder Power Reactor. By D. 0. Lesser, C. K. Leeper,
G. D. Calkins, and D. D. V d o r n . A.to..m.i.c. .P.o.w.e.r. .D.e.v.e.l.o.p.m..e.n.t .....
Associates, Inc., Detroit, Michigan. 307 +
Review of Radiation Effects Studies at the Aircraft Nuclear
Propulsion Department of the General Electric Company. By .. . . .
C. G. Collins. General Electric Company, Cincinnati, Ohio.. 329
c
5
A BRIEF SUMMARY OF RESEARCH ON
RADIATION EIFFE(2TS IN SOLIDS
Members of Solid State Division
Oak Ridge National Laboratory
Oak Ridge, Tennessee
The work summarized in this report is meant to be repre-
sentative of the work being carried on at Oak Ridge National
Laboratory and makes no claim of providing a complete, detail-
ed coverage,
A large fraction of the work has already been reported
in the unclassified or confidential literature and w i l l not
be reported here except by an appropriate literature reference,
Additional lists of unclassified references to OWL work
of a related nature are included throughout the text. For
example, plastics, semiconductors, ceramics, electrical in=
sulation, in-pile and hot lab techniques. There are also
available three unclassified progress reports from the Solid
State Division of ORNL which supplement the discussion, The
reports are: ORNL-1852, 1945 and 2051.
The re search reported herein represents contributions
from a number of sources. In the main, the Metallurgy
Division has provided most of the reactor fuel and related
materials used in the research, The Solid State Division
bears responsibility for the radiation damage studies. The
future work outlined can be int;erpreted as representing the
joint plans of both these divisions augmented by assistance
,
and requests from other research divisions and reactor
projects.
6
Introduc tion
A realization of the fundamental importance of radiation damage
as a critical aspect of a nuclear reactar development program has
lead the Oak Ridge National Laboratory to conduct a broad program
of research in the field. This research functions in a number of
dif f eren t ways
First, through participation in reactor development programs
such as the Homogeneous Reactor Project wherein design and
performance c.ri teria have been specified to the point of performing
reactor tests
Secondly radiatlon effects studies on all classes of potenlAal
reactor materials are studied. These materials may be fuel elements,
structural materials, shield materials, and auxiliary components.
This research aims to develop the engineering know-how and skills
necessary for the proper exploitation of these potential materials.
The development of specifications for usage of materials in a
radiation field is an anticipated objective.
The third aspect of the research concerns itself with the
development of a basic understanding of the radiaaon damage process
including the physical basis of the process; the interaction of
defects with solids and each other, and the temperature dependence
of defect behavior. !he choice of experiments in this case is not
readily translatable into reactor materials engineerlng data, but
it does a b s t always lead to a better understanding of behavior of
reactor materials. The scope of the present report is limited to
the research relating to reactor projects and materials.
Our present information derived from experiments and experience
with reactor operation enables us to anticipate that radiation
damage at low flux and modest integrated exposures does not pose
any insoluble problems except in the most sensitive of materials
that usually are not employed as reactor components.
The radiation damage problems that arise in long range reactor
plans, wherein one anticipates very high fluxes (-ld-5) and
uninterrupted operation extending into years, wiU be unanswered
for sometime because we lack the experimental facilities that vi11
permit us to make radiation damage studies under these conditions.
W e are in the parodoxical situation of not being able to study
radiation damage a t high fluxes until we have a reactor that
operates a t high fluxes. If we are able to attribute all radiation
effects as being sensitive only to total exposure, the situation is
not too bad for several years. If it tarns out that many important
c
7
properties axe flux sensitive then the reactor program may be in
serious difficulty since we are not in a position to extrapolate
orders of magnitude. The eventual burnout of important elements
such as manganesein steel after prolonged exposure may create
additional problems Fortunakly this problem is somewhat
.
limited by the natural distribution and abundance of transmutable
elements
Recently we have begun to focus attention on a class of
phenomena that have recent3y been uncovered which has to do with
the reversion of low kmperature phases to non-equilibrium high
temperature phases under irradiation. To date this behavior has
been observed in ZrO2 and in uranium-molybdenum alloys. There is
some indication that irradiation may change transformation
temperatures in the so-called martensitic reaction. The apparent
anomalous increase in ultimate tensile strength a t irradiation
temperatures where the yield strength increase begins t~ anneal
is also worthy of detailed consideratLon. The necessity of consid-
ering stress environment and temperature as having an important
influence on creep rates under irradiatcion is an important problem.
A cooperative program between the Pletallurgsr and Solid State
Divisions is undertaking a study of a variety of solid fuel
: -
elements (metallic and nonmetallic) as a function of burnup.
~ I . These studies will include both high temperature and low tempera-
ture applicatAons, Studies on control rod material of interest to
e
the Laboratory's reactor program will be studied. It is proposed
to study high density graphite and several stable hydrides for
sui tabiliw as moderator materials. Details of proposed programs
on other materials is to be a t appropriate places throughout the
text.
b s e and related problems suggest that radiation damage
deserves much attention in the next several years if we are to
.
pursue successfully the design and construction of advanced
reacbrs
,
Aluminum-cla aluminum-urani. core fuel elemen,s o tht!
WTR type" have proved successful in the MTFt and other reactors. T
The bel-bearing core contains on the order of 15% (by weight)
of enriched uranium in 25 aluminum, The structure consists of
i
a dispersion of the intermetallic compound UAl4 in an aluminum
mat*. The fabrication cff this type element has been described
by Cunningham and Boyle,
This type of element has prove7 reliable service, even
With burn-ups of greater thn 5$(2 (of the U2% atoms). The
following data and information, however meager, on the physical
and mechanical properties of elements and alumimm-aranium alloys
may serve to indicate the properties required in hture fuel
elements ,
Proof Tests of MTR Elements
Historically, the first important test on a full-size MTR-
type element was performed in 1950. An M'l'R-fuel assembly was
irradiated in the Chalk River reactor central thimble for 6
months. The assembly was returned to Oak Ridge for examination
on February 1, 1951,
Before and after measurements on the outside of the assembly c T'
showed no change (swelling or distortion) within k.005 in.
J
Absolute measurements of the width of the gaps between plates
gave an average deviation from the original measurements of less
than .001 in. The maximum deviation (one point) was .006 in.
There were no visible signs of corrosion, film formation, or
distortion of any kind,
The assembly was irradiated for about 3000 hours at full
reactor power2 , The average thermal neutron flux was about
2 x 1013 n/cm sec.
Subsequent dimensional st s on full-size elements in the
MTR will be described by Bartx
Hardness and Bend Test Data on MTR and LITR Elements
Table I lists the hardness results from LITR and MTR elements
irradiated to burn-ups greater than 2@. Tests were performed on
1/2n wide sections (transverse) of the fuel plates. Bend tests
were performed on a miniature brake. Hardness was measured on
Won machine equipped with a diamond-pyramid indenter.