ML19259B948
| ML19259B948 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 11/30/1978 |
| From: | Cowan R, Gordon G, Walter W GENERAL ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML19259B947 | List: |
| References | |
| 78NED295, NEDC-24159, NUDOCS 7906040218 | |
| Download: ML19259B948 (34) | |
Text
NEDC-24159 CLASS NOVEMBER 1978 DRESDEN 1 RADIATION LEVEL REDUCTION PROGRAM LONG TERM EVALUATION OF THE EFFECTS OF EXPOSURE TO DOW NS-1 SOLVENT ON THE STRESS CORROSION CRACKING OF SENSITIZED TYPE 304 STAINLESS STEEL IN SIMULATED BWR ENVIRONMENT W. L. WALKER 2282 248 7906040 A/1
NEDC-218159 78NED295 Class I November 1978 DRESDEN 1 RADIATION LEVEL REDUCTION PROGRAM LONG TERM EVALUATION OF THE EFFECTS OF EXPOSURE TO DOW NS-1 SOLVENT ON THE STRESS CORROSION CRACKING OF SENSITIZED TYPE 3oli STAINLESS STEEL IN SIMULATED BWR ENVIRONMENT W. L. Walker Approved:
R. L. Cowan, Manager Plant Materials & Process Development Approved-
[M[
Approve :
. M. Gordbn, Manager R. A. Proebstle, Manager Plant Materials Engineering Applied Metallurgy & Chemistry 2282 249
NEDC-24159 DISCLAIMER OF RESPONSIBILITY This document was prepared by the General Electric Company pursuant to a con-tract with the Commonwealth Fdison Company.
Except as otherwise provided in such contract, neither the General Electric Ccmpany nor any of the contributors to this document nor any of the sponsors of the work makes any warranty or representation (express or implied) with respect to the accuracy, completeness, or usefulness of the information contained in this document or that the use of such information may not infringe privately owned rights; nor do they assume any responsibility for liability or damage of any kind which may result from the use of any of the information contained in this document.
11
NEDC-24159 TABLE OF CONTENTS Page ABSTRACT ix 1.
INTRODUCTION 1
2.
SUMMARY
3 3
DETAILED DISCUSSION 3.1 Material 4
3.2 Specimen Configuration 4
3.3 Specimen Exposure 5
3.4 Specimen Examinations 6
4.
RESULTS 7
5.
CONCLUSION 12 6.
REFERENCES 32 DISTRIBUTION 33 2282 251 iii/iv
NEDC-24159 LIST OF ILLUSTRATIONS Figure Title Page 1
As-received microstructure of heat no. 78500 14 2
Response of heat no. 78500 to sensitizing for 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br /> 14 at 6750C (12500F); ASTM A 262, Practice A, etch 3
Bent beam specimen drawing 15 4
Uniaxial tensile specimen drawing. Dimension "D" is 15 adjusted to give desired stress level 5
Assembled bent beam specimen pair on stainless steel 16 radius block 6
Uniaxial tensile specimen loading module 16 7
Scanning electron photomicrographs of surface of demineralized 17 water control uniaxial tensile specimen exposed to BWR environment at 125% of 0.2% yield strength 18 8
Scanning electron photomicrographs of surface of NS-1 uniaxial tensile specimen exposed to BWR environment at 125% of 0.2% yield strength 9
Scanning electron photomicrographs of surface of demineralized 19 water control uniaxial tensile specimen exposed to BWR environment at 100% of 0.2% yield strength 10 Scanning electron photomicrographs of surface of NS-1 20 uniaxial tensile specimen exposed to BWR environment at 100% of 0.2% yield strength 11 Scanning electron photomicrographs of surface of 21 demineralized water control uniaxial tensile specimen exposed to BWR environment at 75% of 0.2% yield strength 12 Scanning electron photomicrographs of surface of NS-1 22 uniaxial tensile specimen exposed to BWR environment at 75% of 0.2% yield strength 13 Scanning electron photomicrographs of surface of 23 demineralized water control bent beam specimen exposed to BWR environment at 2% strain 14 Scanning electron photomicrographs of surface of NS-1 24 bent beam specimen expcsed to BWR environment at 2%
strain 2282 252 v
NEDC-24159 LIST OF ILLUSTRATIONS (Continued)
Figure Title Page 1$
Longitudinal sections through demineralized water control 25 and NS-1 uniaxial tensile specimens exposed to BWR environ-ment at 125% of 0.2% yield strength 16 Longitudinal sections through demineralized water con!.rol 26 and NS-1 uniaxial tensile specimens exposed to BWR environment at 100% of 0.2% yield strength 17 Longitudinal sections through demineralized water control 27 and NS-1 uniaxial tensile specimens exposed to BWR environment at 75% of 0.2% yield strength 18 Longitudinal sections through demineralized water control 28 and NS-1 bent beam specimens exposed to BWR environment at 2% strain 19 Lightly etched high magnification photomicrograph of 29 tensile surface of NS-1 bent beam specimen 20 Scanning electron photomicrograph of inside diameter 30 surface of pipe heat no. 78500 in as-received condition, showing intergranular attack 21 Typical uniaxial tensile specimen location in pipe mid-wall, 31 with all gage section surfaces fully machined 22 Idealized possible locatior.s of bent beam specimens in pipewall 31 2282 253 vi
NEDC-24159 LIST OF TABLES Table Title Page 1
Composition of Type 304 Stainless Steel Test Material 13 2
Mechanical Properties of Type 304 stainless steel Test 13 Material 3
Distribution of Intergranular Penetrations at Four 13 Locations Across the Width of Two Bent Beam Specimens 2282 254 vil/viii
NEDC-24159 ABSTRACT Tests were performed to evaluate the effects of a proprietary Dow Chemical solvent (NS-1), which is to be used in the chemical cleaning of the Dresden 1 primary system, on the stress corrosion cracking behavior of severely sensitized Type 304 stainless steel in oxygenated high purity water.
Rectangular ber.c beam specimens and cylindrical uniaxial tensile specimens were given a severe sensitizing heat treatment, exposed to a simulated NS-1 cleaning cycle in the unstressed condition, and then exposed for 13,503 hours0.00582 days <br />0.14 hours <br />8.316799e-4 weeks <br />1.913915e-4 months <br /> to a simulated Boiling Water Reactor (BWR) primary coolant environment in the stressed condition.
No evidence of stresa corr 03 ion cracking was observed in this investigation.
2282 255 ix/x
NEDC-24159 1.
INTRODUCTION A large corrosion test program has been associated with the proposed chemical cleaning of the Dresden 1 nuclear power plant primary system surfaces to reduce the radiation exposure associated with the required inspections. The solvent chosen for the cleaning operation was a proprietary compound, NS-1, formulated by the Dow Chemical Company and a considerable amount of corrosion testing was performed by Dow in the process of the development of this solvent (Ref-erence 1).
However, in the course of the review of these data it appeared that some additional special tests were required to assure that all questions related to the effect of the Dow solvent on the Dresden 1 structural materials had been fully addressed.
Past work conducted by General Electric Company's Nuclear Energy Engineering Division (NEED) in San Jose, California, has produced evidence that, under certain circumstances, short term exposures to specific corrodants at moderate temperatures can have very significant effects on the intergranular str ess corrosion cracking (IGSCC) behavior of sensitized Type 304 stainless steel when subsequently exposed in the stressed condition to oxygenated high temper-sture high purity water. The corrodant. which have produced this effect have been strong inorganic acids with significant quantities of hydrofluoric acid present. Exposure to strong inorganic acids without the presence of hydro-fluoric acid has not resulted in enhanced susceptibility to IGSCC in the tests performed to date, and the general effect has been called the " pickling effect" because of the apparent association with the fluoride ion. However, extensive testing to determine the mechanism of the pickling effect and to clearly demonstrate that it is specifically associated with the fluoride ion has not been performed.
In the absence of such definitive testing, it has been necessary to adopt the conservative position that <ny acid solution might be capable of producing the pickling effect, and to prohibit the exposure of austenitic stainless steels to acidic solutions, except in the solution annealed condition. This position has been implcmented in NEED purchase and installation specifications for several years.
As stated previously, the composition of the proposed solvent (NS-1) for the Dresden 1 primary system cleaning operation is proprietary to the Dow Chemical Company, however, NEED has been informed that it does conta or organic 1
NEDC-24159 chelating and complexing agents, and has a pH of 3 to 4.
In the absence of information to the contrary, it was believed that tests to evaluate the presence of a possible pickling effect from this solution were necessary in order to assure that no serious deleterious effect resulted from exposure to NS-1.
This report presents the results of the investigation into this question.
2282 257 2
N KDC-24169 2.
SUMMARY
Multiple specimens of furnace sensitized Type 304 stainless steel were exposed to a simulated cleaning cycle in "used" Dow NS-1 solvent, and then to 13,503 0
hours in a simulated BWR environment; 0.2 ppm oxygen, ;?880C (550 F) high purity water. Five specimens were exposed to NS-1 and then strained 2% as bent beams during the subsequent BWR exposure, and six specimens each were exposed to NS-1 in the unstressed condition and then exposed to the BWR environment aa uniaxial tensile specimens at stresses of 75%,100%, and 125% of the 2880C (5500F) 0.2% offset yield strength.
Duplicate sets of control specimens were exposed to 1210C (2500F) demineralized water, and then to the BWR environment.
Interim optical examinations were made during the simulated BWR exposure, and final scanning electron microscope and destructive metallographic examinations were made following the 13,503 hours0.00582 days <br />0.14 hours <br />8.316799e-4 weeks <br />1.913915e-4 months <br /> exposure. No indications of stress corrosion cracking were observed on any specimen. The cata generated in this investigation indicate that exposure to Dow NS-1 does not produce a significant increase in the susceptibility of sensitized Type 304 stainless steel to intergranular stress corrosion cracking in subsequent BWR service. Some shallow intergranular penetrations were observed on the bent beam specimens, but these penetrations were shown to be original intergranular attack on the inside diameter surface of the pipe which occurred during its manufacture.
2282 258 3
DETAILED DISCUSSION 31 HATERIAL The heat of material chosen for this investigation (Heat No. 78500) was selected on the basis of its susceptibility to intergranular stress corrosion cracking (IGSCC) in constant load tests performed at higher stress levels in oxygen-saturated high purity water at 2880C (5500F) (Reference 2), and the ability to machine all required specimen configurations from the as-received material.
The original configuration of the material was 15 cm (6 in.) Schedule 80 pipe, with the composition and mechanical properties shown in Tables 1 and 2 respec-tively. The as-received microstructure of this heat is shown in Figure 1.
All specimens were tested in the furnace sensitized condition - 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br /> at 648oC (12000F), furnace cool - and the response of this material to an ASTM A 262, Practice A, test after heat treating is shown in Figure 2.
3.2 SPECIMEN CONFIGURATION Two specimen types were used in this investigation; fixed deflection bent beams and uniaxial tensiles, shown in Figures 3 and 4 respectively.
Six bent beam specimens were exposed to NS-1 prior to the simulated BWR exposure and six specimens were exposed to 1210C (2500F) demineralized water to act as controls; all in the unstressed condition. The bent beam specimens were then stressed by bending them over solid fixed radius blocks, with a radius chosen to produce 2% strain in the outer fibers of the specimens, as shown in Figure 5, prior to the long term sinulated BWR exposure.
The uniaxial tensile specimens were not stressed during the NS-1 and demin-eralized water control exposures, but were exposed to simulated BWR service environment as constant load specimens stressed to 75%,100% and 125% of the 2880C (5500F) 0.2% offset yield strength of the material. The specimens were loaded into the test modules shown in Figure 6 and stressed by internal autoclave pressure, with the diameter of the reduced gage sections adjusted to give the selected stress levels on the specimens. Five specimens for each stress level were exposed to NS-1 prior to the simulated BWR exposure, and five specimens were exposed to 12100 (2500F) damineralized water to act as controls.
2282 259 4
NEDC-24159 33 SPECIMEN EXPOSURE The solution used to simulate the cleaning cycle was Dow NS-1 with additions
- 12 H 0] and 2.9 of 10.4 grams / liter ferric ammonium sulfate [FE(NH )(SO )2 4
4 2
- 6 H O) to simulate the solvent at the maximum grams / liter nickel sulfate (NiSO4 2
allowable iron and nickel concentrations of 1200 ppm and 650 ppm, respectively, specified for the cleaning operation ("used" NS-1).
The initial exposum of 0
specimens was to a cycle of approximately 100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> at a temperature of 121 C 1 50C (250 F 3 100F), with one set being exposed to "used" NS-1 and the control
~
set being exposed to demineralized water.
All 12100 (2500F) specimen exposures were performed in a TFE (tetrafluoroethylene) flourocarbon-lined pipe spool piece, with TFE-lined blind flanges, to avoid contamination of the solution with extraneous material.
Solution volume-to-2 surface area ratios were approximately 401/m ( l gal /ft ) during both exposures, and both solutions were essentially air-saturated at the time of initial immersion of the specimens. No attempts were made to remove oxygen from the solutions prior to insertion of the specimens because, at that time, the intent was that no degassing operation would be performed in conjunction with the actual plant cleaning operation. This position was subsequently changed and a nitrogen sparging and blanketing step was added to the plant cleaning procedure. The variance of the test procedure from that eventually planned for the plant cleaning did not represent a significant difference from the standpoint of the purpose of the test because, if anything, the presence of oxygen would tend to increase the probability of the occurence of intergranular corrosion of sensitized Type 304 stainless steel.
Following the NS-1 and demineralized water control exposures, the specimens which had seen NS-1 were rinsed lightly with demineralized water to remove residual solvent. The bent beams were paired on their radius blocks and plas-tically deformed by bolt loading, and the uniaxial tensile specimens were loaded into their test modules. All specimens were then exposed to simulated BWR service in water containing 0.2 1 0.1 ppm dissolved oxygen, with a conductivity 0
0 of less than 1.5 pmhos, at a temperature of 288 C 1 5 C (550 F i 10 F). Flow rate through the autoclave was 50-60 cm3 min, and conductivity was continuously
/
monitored.
Daily measurements of dissolved oxygen and pH were made and recorded.
Total exposure time was 13,503 hours0.00582 days <br />0.14 hours <br />8.316799e-4 weeks <br />1.913915e-4 months <br />, except for single bent beam specimens 2282 260
NEDC-24159 from each group which were removed for metallographic examination at 11,700 hours0.0081 days <br />0.194 hours <br />0.00116 weeks <br />2.6635e-4 months <br /> for purposes of another investigation (Reference 3).
3.4 SPECIMEN EXAMINATIONS Periodic examination of the specimens was not a planned part of the program.
The intent was to perform ex,aminations whenever a constant load uniaxial specimen signaled a failure. However, only one such event took place at approximately 600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> exposure, and that event was a falso signal of failure. The bent beam specimens were examined optically at magnifications up to 30 diameters after the false failure signal at 600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> exposure, and during an autoclave repair outage at 12,924 hours0.0107 days <br />0.257 hours <br />0.00153 weeks <br />3.51582e-4 months <br /> exposure.
No interim examinations of the uniaxial tensile specimens were made because of the difficulty in removal and replacement in the test floture, and their capability of signal of failure.
As mentioned previously, a single bent beam specimen from each of the NS-1 and control sets was removed and subjected to destructive metallographic examination af ter 11,700 hours0.0081 days <br />0.194 hours <br />0.00116 weeks <br />2.6635e-4 months <br /> exposure to confirm the absence of general intergranular corrosion resulting from the NS-1 exposure. An additional 579 hours0.0067 days <br />0.161 hours <br />9.573413e-4 weeks <br />2.203095e-4 months <br /> exposure was accumulated, for a total of 13,503 hours0.00582 days <br />0.14 hours <br />8.316799e-4 weeks <br />1.913915e-4 months <br />, prior to an extended test facility outage for instrument calibration and system modification. At that time, the tests were terminated.
Following the 13,503 hours0.00582 days <br />0.14 hours <br />8.316799e-4 weeks <br />1.913915e-4 months <br /> exposure, all specimens were examined optically at magnifications up to 30 diameters, with the bent beam specimens still stressed on their radius blocks. Single specimens from both the control and NS-1 groups were then examined by scanning electron microscopy (SEM) at magnifications up to 1,500 diameters. Finally, destructive metallographic examinations were performed on specimens subjected to SEM examination.
2282 261 6
NEDC-24159 4.
RESULTS As indicated previously, the only indication of Stress corrosion cracking failure of a specimen during the 13,503 hour0.00582 days <br />0.14 hours <br />8.316799e-4 weeks <br />1.913915e-4 months <br /> simulated BWR exposure proved to be a false indication.
No failures of any type were observed during the course of the long term exposure.
Optical examinations of the specimens following completion of the BWR exposure gave no indications of the presence of stress cerrosion cracking. However, several bent beam specimens from both the control g"oup and the NS-1 group exhibited areas of oxide which appeared to reflect the underlying grain struc-ture of the base metal. Photographic resolution cf these areas did not prove possible because of the subtle contrast differences which were visually apparent.
There did not appear to be any significant difference in this respect between the control specimens and the NS-1 specimens, and the effect was classified simply as a testing artifact.
The as-tested surfaces of single control specimens and specimens which had been exposed to NS-1 prior to the long term BWR exposure from each test group were subjected to scanning electron microscope (SEM) examination. All specimens exhibited normal high temperature water corrosion product films, and no indi-cations of intergranular stress corrosion cracking were observed. Typical surface conditions are shown in Figures 7 through 14.
Following the SEM examinations, the specimens were sectioned at their approx-imate midplanes and longitudinal sections were mounted and polished for each specimen. The uniaxial tensile specimens exposed at 75%,100% and 125% of the 2880C (5500F) 0.2% offset yield strength all exhibited normal surface conditions with continuous oxide films and no indications of intergranular stress corrosion cracking, as shown in Figures 15 through 17, respectively. Similarly, no indi-cations of intergranular stress corrosion cracking were observed on the demin-eralized water control bent beam specimen, as shown in Figure 18.
- However, a number of shallow intergranular penetrations were observed on the bent beam specimen which had been exposed to NS-1 prior to the simulated BWR exposure, as also shown in Figure 18.
2282 262 7
NEDC-24159 The intergranular penetrations observed on the NS-1 bent beam specimen differ from typical intergranular stress corrosion cracking penetrations in a number of ways. First, the penetrations are filled with oxide which is continuous with the surface oxide film, as shown in Figure 19, and this accounts for the lack of their observance during the SEM examination.
Intergranular stress corrosion cracks have invariably shown discontinuous corrosion product films at the surface, and a discontinuous film is a requirement for stress corrosion cracking in the currently accepted models because there must be a path to the crack tip which permits access of the corrosive fluid. Second, the tips of the intergranular penetrations are blunted while intergranular stress corrosion cracks have consistently shown sharp crack tips. Finally, if one assumes that the initial penetrations were the result of intergranular stress corrosion cracking, then one must conclude that the propagating cracks arrested for some reason and that general corrosion of the exposed crack faces resulted in the blunting of the crack tip and the filling of the crack with corrosion product.
To the best of this writer's knowledge, this situation has not been observed in any of the service failures or laboratory test failures of sensitized Type 304 stainless steel. None of the characteristics of the penetrations observed on the bent beam specimen are consistent with those associated with intergranular stress corrosion cracking, except for the intergranular nature of the penetrations themselves. The evidence would indicate that the intergranular penetrations were present on the original specimen surface prior to exposure to the simulated BWR environment, and may have been present prior to the exposure to the NS-1 solution.
The most probable source of intergranular penetrations on stainless steel piping is the pickling operation at the manufacturer's shop, and numerous instances of such intergranular attack have been observed in the past. The attack occurs as a result of either an improperly controlled pickling bath, or surface carbu-rization of the pipe during some step in its manufacture. The inside diameter surface of the pipe from which the specimens for this program were fabricated was examined, and intergranular attack was observed in the as-received condition, as shown in Figure 20.
However, the bent beam specimens were machined on all surfaces prior to testing in order to produce a uniform starting surface con;1 tion.
If the observed intergranular penetrations on the test specimen were caused by pickling attack during manufacture and insufficient material was removed 8
NDC-24159 by the machining operation, then one would expect them to exhibit certain charac-teristics. First, they should be relatively blunt penetrations because of the very aggressive nature of the pickling solution. Second, they should be filled with a continuous corrosion product fibn af ter long tens simulated BWR exposure because the side walls of the penetration would corrode at the same rate as the general surface of the metal, and there would be no driving mechanism for further separation of the relatively close walls of the original penetration.
Third, the density of penetratians should change in a predictable manner as one examined different sections through the same specimen, and the observance of such penetrations should be a sporadic occurrence on only the bent beam specimens because of the manner in which the specimens in this test were machined and tested.
The reduced gage section of all of the uniaxial tensile specimens would be located at the approximate mid-wall region of the pipe, as shown in Figure 21.
Machining in this m' aner would have removed all traces of any original inter-granular attack fram the finished specimen because no tested surface would have been near the original inside diameter pipe surface. One would not expect to observe any intergranular penetrations on the tensile specimens which was the result of intergranular attack during the fabrication of the pipe. However, the machining of the bent beam specimens does present the possibility of the retention of original manufacturing intergranular attack on one surface of the finished specimen. As shown in Figure 22, a bent beam specimen can be machined from one of three general locations; near the outside diameter of the original pipe, in the mid-wall area, and near the inside diameter of the pipe. The situation which would produce a specimen with intergranular pene-trations on an as-machined surface would be one in which the specimen was machined from near the inside diameter surface, as shown in Figure 22-C, and the manner in which the bent beam specimens were machined would tend to maximize the prob-ability of one surface being near the original pipe inside diameter surface.
The specimens were machined in the following sequence of steps. First, a longi-tudinal section of approximately the 1 2ngth and width of the finished specimen was saw-cut from the pipe. Second, the rough blank was placed on the milling table with the inside diamcLer surface down, and one major face was machined flat. The amount of material removed from the outside diameter surface would 2282 264 9
NEDC-24159 depend upon the degree to which the blank sat " flat" on the table. After machin-ing the outside diameter surface, the specimen was turned over and the inside diameter surface was machined to the final thickness. Finally, the sides of the specimen were machined to the final dimension.
The amount of material removed from the inside diameter surface would depend upon how much had been removed from the outside diameter surface. The probability of any original surface remaining on the outside diameter specimen face would be near zero, because of the curvature of the pipe surface. However, the probability of some original surface remaining on the inside diameter specimen face would appear to be significant, but of unknown magnitude because of the interaction of the two variables of the original specimen blank geometry and the amount of material which was removed f rom the outside diameter surface during the first machining operation.
Furthermore, even.T every bent beam specimen had some vestige of original intergranular attack on the inside diameter specimen face, the probability that the inside diameter face was stressed in tension would be only 0.5 because no identification of original specimen on.ientation was maintained. The combination of the uncertainties related to the physical location of the specimens within the original pipe wall, and the particular specimen face stressed in tension, made destructive examination of all specimens a questionable procedure for the resolution of the source of the observed intergranular penetrations.
A definitive method for demonstrating that the source of the intergranular penetrations was original pickling attack at the mill involves the distribution of the penetrations on the specimen.
If the penetrations represent original intergranular attack, then a maximum density of penetrations should be observed at some point on the specimen and should decrease to zero toward the edge (s) of the specimen. This would result from the concave nature of the inside diameter surface, with more material being removed from both edges of the specimen than from the center during machining. Stepwise polishing and etching through the specimen width would provide the necessary information.
The original mounting instruction for the specimen shown in Figures 18 and 19 called for sectioning through the approximate mid-width plane, and the precise location of the sectioning cut was not recorded.
It addition, the amount of material removed during the initial polishing operation was not measured, 228;2 265 10
NEDC-24159 so it was not possible to ascertain the precise location of the plane examined or the amount of remaining material.
A single incremental step grind of 0.13 cm (0.05 in.) was made and the specimen was repolished and examined. No change in density of intercranular penetrations was observed, but there was also no significant change in the maximum depth of 1 x 10-3 cm (0.0004 in.).
Fu rthermore,
there were no indications that the intergranular penetrations observed were continuous through the distance removed. One would not expect this observation if the penetrations represented intergranular stress corrosion cracking.
It was considered desirable to retain as many of the specimens as possible in their as-tested condition until the question of the source of the intergranular penetrations war resolved. For this reason, no additional specimens were mounted for sequential sectioning and polishing.
Instead, the two specimens which had been removed after 11,700 hours0.0081 days <br />0.194 hours <br />0.00116 weeks <br />2.6635e-4 months <br /> exposure were used for further investigation.
These two specimens, one control specimen and one NS-1 specimen had been mounted on an original side face and polished, with only a small amount of material removed frot the full width of the original specimens. The specimens were ground and polished in three sequential 0.13 cm (0.05 in.) irarements, and the number of intergranular penetrations and their locations were recorded for each section examined. The results are shown in Table 3 The data shown in Table 3 exhibit the types of patterns which would be expected to occur if the intergranular penetrations observed were the result of original intergranular attack of the pipe inside diameter surface during its manufacture.
The density of per._.trations changes from a minimum to a maximum as one examines successive sections across the width of the specimen.
In addition, there were no indications that any of the penetrations were continuous over the distance moved across the specimen width. These observations would appear to represent conclusive evidence that the observed penetrations were caused by a pickling operation during the manufacture of the pipe.
2282 266 11
NEDC-24159 5.
CONCLUSION The results of this investigation do not indicate the presence of a significant deleterious effect of exposure to Dow NS-1 on the stress corrosion cracking behavior of sensitized Type 304 stainless steel in subsequent exposure to a simulated BWR environment over long periods of time. One cannot make a statistical statement as to the confidence associated with this conclusion because no failures occurred in either the NS-1 group or the control group. However, the tests were run under conditions in which the presence of such an effect has been observed in previous studies performed by General Electric Company's Nuclear Energy Engineering Division.
2282 267 12
NEDC-24159 TABLE 1 Composition of Type 304 Stainless Steel Test Material C
Mn P
S Si Ni Cr 0. 04 3 1.63 0.019 0.01 3 0.53 9.00 19.05 TABLE 2 Mechanical Properties of Type 304 Stainless Steel Test Material Test Temperature 0.2% Y.S.
UTS
% R.A.
% El.
Ambient 235 MPa 549 MPa 81.8 74.8 (34.1 ksi)
(79.6 ksi) 2880C (550 F) 136 MPa 426 MPa 74.6 50.8 0
(19.7 kai)
(61.8 kai)
TABLE 3 Distribution of Intergranular Penetraticna at Four Locations Across the Width of Two Bent Beam Specimens Number of Intergranular Penetrations Section Polished Control NS-1 Original 0
0 0.13 cm (0.05 in.)
0 10 0.26 cm (0.10 in.)
9 12 0.39 cm (0.15 in.)
7 4
All penetrations were less than 1 x 10-3 cm (0.0004 in.).
2282 268 13
e
\\
\\
~ /,.
t J
p.
N. w.
.d 250X Figure 1.
As-received Microstructure of lieat No. 78500 F.aCA 4/. Qs M'A e M,F<
.,.?
w....
. k:
- f?-
' ?
- A,., 4
[y s'
1-e-
o e
j^ f.
h 3f, 1
- # g,
-a *
' ?sL
{;j. %, l p e.
.-;r o
A
.,{
s e,, * > :
,\\
q oy
[..., -
r2 s
a
- Y-o. </
' '. (* 4
/~
f.[,.
,,4' f
250X Figure 2.
Response of Heat No. 78500 to Sensitizing for 50 liours at 675 C (1250 F); ASTM A 262, Practice A, Etch h
14
8.7cm (3.43 in )
T 1.27cm (0.50 in) i e
1 10.5 cm (4.12 in.)
l lll 0.76cm I
i (0.30 in.)
l l
Figure 3.
Bent Beam Specimen Drawing 5.72cm n
(2.25 in.)
)
h 1.27cm Dia.
(0.50 in.)
(
..o..
1.27cm R THREAD (1/2 20)
(0.50 in.)
r BOTH ENDS 1.11cm (0.44 in.)
2282 270 Figure 4.
Uniaxial Tensile Specimen Drawing (Dimension "D" Adjusted to Give Desired Stress Level) 15
$PECIMEN p
2.5 cm 3
(I nn.)
O MINIMUM CONTACT LENGTH l
Figure 5.
Assembled Bent Beam Specimen Pair on Stainless Steel Radius Block
^
NUMBERED FAILURE SSUR E
/~
m INDICATOR BALLJ\\gN1\\\\\\\\(
/
O'<M/ e eLl7!
/
mww 1uv TENSf LE SPECIMEN
\\
AUTOCLAVE PR ESSUF'E
' MANIFOLD O
1 N
V 2282 271
'^^
4 o
TO ATMOSPHERE Figure 6.
Uniaxial Tensile Specimen Loading Module 16
^ 3a [M*M.N *[,".-E [;;T, k fdMhf.hkN%[. MJ f88i@di$N., $.e$$$,1d$ inh 5$k$y$E'Ik p
" O,,.f.a.m.
- w;, c :q'p'l8:'.. ;-,u, r.,. n! /:.:..M s,,..,n.n cs
.. s.<s.+ ::
_- t
.w.,
fk.1k, t ;.n N..p,
(
-f. '%.' ?;Q.Q,qQ$Rilp?l4,1 fy{i*-
6@ sy(h;.dL'.* T. y s
,? 3 y!
- M W
. - Q y,v y,;j%
'Eg. %Ts,,? *:ve'L'.p., <. t. W i i g, 90 z t a.;f,+'g.,p?
, g-y. g s,.3.'. -
rN;
- g. Q 'a
's ; ;,2f %:
2
\\
ki
<tyyq's,?R${[ h-,' !A ih9q>X; ^'$m$k.wn$y9,U
h
cA N e.
. - x w amm.c.::%w'.n.,:- 7.y, ** > :y y,&...g d' e
0;ts:v,g g f.Q) f','hNb'$Y i 'N 'Yhb5 IEs$SES$NMENS$bb.S'NY$b UMhb[$k i$$109%mphw;%
hh.j[D$5f5QMSNM$U-:s c.
,,3-kg. *~):y.*@?', 's *-e,\\* N(-..35 E*."$3'.
b..'E g J.:h'h=.f*$
- &&;.:iT*,QY t
A ',
- 'l vc t
- 7. s
--' d-Y'b. _tdE$'l M
100X e,. 4. k'~ r i#.d g
y
., _ s.,
..g
{s a's*'m%
es h. s.. s%,w&q., g w
r fjif +3.,gf'?,
Q.
m
' p' I
a ew p%g:
~
Yd hbb 500X 1500X 2282 272 Figure 7.
Scanning Electron Photomicrographs of Surface of Demineralized Water Control Uniaxial Tensile Specituen Exposed to BWR Environment at 125% of 0.2% Yield Strength 17
NEDC-24159 Q,r:uv?q hQ-hh.W Q :'~.n-
- W[i y$ n:),b)c.((,u,;db;>~d.cf -[Y.
va r--
n x e c c y )..--s I
.l.
,% %c
- *22y4 c 1 r.ti6,';:%y ? '5 % 4. *~n' *-9 ? $'.1SQ Q
'*a ; :f.c;.; ~r 4
rq.-
'.. t WV : W:n Q s.< ~ u.f.s-g.x%.,.. c,yg.1sw w a..? %.,g:s>.# w;, c n:
.n u.3 a
1 1
. mr; 1
- w. q L 9.l,C,ky k
- q N%i.';6.-Nlf [,..g.;,..
% 4.3r.i. Le
'a'. # 'O' -
- 1'
': ' d e-
,-Q,oQ.'i.Q* * :v.~.'[,;'"Y-d h,'!b.- <.~-]..*',j q O rN f
%x%yNq v.k;,..
. '..2:,,-,:i :s.:.., h.. * ?. "
".v & Bing%i!,;. -% % p,% Q'm
- K{p
- . 7 M e-i
.A4 m..
.. v.,
f 3 a p R c.q ? Q[ 9 ' E ' W e t# %
p3
%;6ED 4t gs 7 9 4;3;.~; m c o n,y g tj.
ep4 t,os e t;.
a.w. s hh b
p%n$-y;Mf.%../ fib'8Eff4.$
)
i' n
- nid%4:r h'~
h*
h
'g'NI$?h Nib'h)NE/N h9 i[d$Nl@kN ON/fdA9*Wys;g.
't.$'J N.9'd 'D3.h g di4i 9EfW R
'a A
f 100X gg,%g/ v 2 7 y 4,g A ~.J I.-
k.
r
,o 500X 1500X 2282 273 Figure 8.
Scanning Electron Photomicrographs of Surface of NS-1 Uniaxial Tensile Specimen Exposed to BWR Environment at 125% of 0.2%
Yield Strength 18
.s@,..,>n::;;&y:'.:.M,;w >,&:.M*h'f's Ye,'qple.,2{ hQ. " '7-@.Y,7'l; '( -
<.%.f' C' N'*
- (.rlQ*. :
D..y - 'J. *.
. h,*9,
'F '
~ 4. '
..y &.,~:y G. @A s. v, n.4
!,v,m.S!E,.M,..~M.e,...c,.S.EM.r.Em.%..
. w,,,,. M.
W; e g..., o,:.,.
r
.s:.
- m.yy.s;e.e.
- e p s m.n M.x.p.,....
.. m 3..
m,
~.s.
,.e...
m.
. c
. m..
s kab.,.N.w'* f..>.3' ?:.u.a.s..
,. v.;.
1.. '.4. c... " ; '~^ r 'W "r m. -.,7.-P.,o!'w.,, _k..
o.,u".*,,."<
c.
"l,, ~,, L' f."3 p e<,.w.,.'.,.y
[g '[',' ',JS41;*! K';'. i.. %i ",* *, ' b: s, 3..,.,. y, -, %.' -];r4l,: c'(
s,+
s;
!16
%.. d"p. 4~..
, n.s
- a., Q %. r, f.4
.M < y 3, s.. 3: -
.. r.-
!;..n c g::av',,.U =,..;.N..' s.. ; 7 3 1. '.... w:u
... - e' k.. ;4,
i '
. J.' mI.*J.?'i* 5.Ji M rm p
%. s. -'.;.;~m:o*
s.#' >,((4 ) '
h v.
'.,,,.r, v.
.w,.,.,
y:. ~, x{;c c.. i'
~ C t a'
.,..'2I ' 'Y 4 ~,.* i j, d...h I ' e
...x.,.,,.
,u
- w.... g,,.~.... g, ~. -.../.,,,-'
v',.. > c. -
+
+.+,,s w m.
.. ~. ; w. +.u.e.
=
+
- .,. m o g. y.. c
_.s. <...,
'Eh Nb...S.
c' E
'd. d *. T $ i ' s..
. '. h.
100X IN.,w,.b; Y
~
p.
a WiC %'
Q 5%si'4 tg 2
~ ' * +'
- s er.r.
Y [
=:. o;hrsp 6'%
X iP 3 g$M y#'
s 8
e ygg.,t :,. ;
,w&g %~
qa.
A fr
+
,m Jy w tc 500X 1500X 2282 274 Figure 9.
Scanning Electron Photomicrographs of Surface of Demineralized Water Control Uniaxial Tensile Specimen Exposed to BWR Environment at 100% of 0.2% Yield Strength 19
.,v s :
a.~.
y.
n. -~;. z.:... -c.4.y :,
. c.
f weye
'.. p w 9v;,.,...:: % >S p =g a.
w.~. -
n s
.,,9
,.T.u
.* pe ",..y,p'3, q.s,% d.e,?r.t.
w.
-l
.....,.v
~
M e.~. %m -.;,y p' 4 +* c~:. ~;m. w;. g.p; >m
- ~ c:-
,,A~*. <%..
.<ip, -
w. 4. g.., J -
n y.
.: +%- m i uR,,,.;..;p%w',',;
.. <:..v- %
r, m.> s 4.,. 7 %. n.-t~ v.,. 6.. c.
...r, %.,
u.~
- >y.v* '.4rf.'.Y b.
- y-R ' #l2.- %M,;,.) *;; '/,,'..-i. ;c'f'.@a. T _ :.D M
.c.
... W
.t p
. m.,.,,e-
. - -m
. g..
.z :, -
- e:
m-
.+,
. 5. Ae'o;.,s.y., s;..,...,.
L tG:.?:, lQ: rd.: 'a"~;~.T:~.~c,i y,,;.t.t -. :.,.,%, : - :~;'
.n
. e 3.;.g.:..
m
..z'n e :%.m.r:%.p.Q Ki%.k; c*f;,~,. ::.q';. ;.'..;:.m.;. a.f,x~
4 3 92
.- -as%
~.
%~.-
J.% y.:. :p.: :q..> : ~9:
W.m..,:s~~-
n:. ; -
- v hv.s.:4 >A;,
hu6
'2 dnN.p.4%;$;:g
.t,)a::* ::~M.<1~e'.n%..'..%
~.
+ Q,, *g.~f* JQ.,. v % : u -:\\..
2.f yt;Q~.,,,,:s.c:.n,,71Q,:.. o.-Q
=.
~
--s-Ja s n-
,e-Reld., y%p;Mx -e..,f,.:..p.:ig ~3 4-. *,.,p:;gy 4. :.c;,f W'/.%,y ?%.;.
- a..
39r N'*@= c,;
g
,.. w sry m.s.
.u, s~
,v (Y,,&gpe7d' 8 ;.*A, >.62.:
C m..
~ M:m M@$'f.M..P
- a.
~
cy-,t ~s en
" :KY
$:/ d.VldyEl'C2ii',h.
gvQ%;.y.-
~.,vjy \\ u. :-
yr
.s c%.*
M)E...-$fS$..-a c&g.y..%. ;x...m.~r.e.g;.e.L u y.a t.$.
% g.
~.
5.h WMs
~ w. m.s.r. 4.. h *1.k U.1 C, h W 9 s e t t
kQ 2.V~
+helInd * - t.'.,
N%
..-s e., 4... w.~. +.,::s..r.,+,t. A.,s,.w 4.,
.,w.
w e
x
.r.
100X A
hk?k fkk@Mf w y rm&.
.ne}L r
swsw qfgf,m%u.an:.y.y p L:
%g 'k'ifw.
4, y
n.
EWGE. c-w:a:se.y@9hA SQ.
?
a eslf **),m':,%'1.g:n 2.N.c icy
- G.*%w' 'y' l \\ ijid
- 1 C-1,P t r W' V,. Tyy?,;
.?:-[
%.n yt
- fem 4,, hw: :-$ 9 s n g p ig S
M e.s
~ l'.
mN.
tG?g.n. !,. % >"'.c
., r[,[g.
. s Av
~
t' I
_~ ".
J 500X 1500X 2282 275 Figure 10.
Scanning Electron Photomicrographs of Surface of NS-1 Uniaxial Tensile Specimen Exposed to BWR Ensironment at 100% of 0.2%
Yield Strength 20
- * -l.hs iG.f.%. w!,'i.?ol.. p,s, rgM. aM.
..,,. s., e
- 6.. 9. ---y,4ss$d, o...
T:":.u:4.,.f..n.:,
~
. ~,..
q.
v
- h.:l + n.;-n
~
kW?'s.t.h.y;../;;i.: ". i'.W.
' 6 ;.. * - %
t.',.
,.s 3.Q *
% a,* ;;"; 3 X. 'u....;@... c.
~.,-y: ( " ~: %. %,.;g,b.,.,-
4.. g..M.
- m,
. *t; q
s 3?n c,.
- .v,.
.c..
c,_ay v.t. q.,.+., e..:..,...:-...s,...g:7.,.qq.m.,.
..w.
.n.
..,, m,.,,.. w....
s'.. c. n.v+...c.m...
....,.e
_.... c.
m
.. y -.
sa. ~. v.
x.
.. n:
owa<ys. > ~.
w y, s
..y q.,'.,,-~
... A.' x-, w m x y_f.t..q
.is%..m p%::. D,..,,., r.:
qA..%g;%..;,.
M:gg,%-J" O 2
.s'..i: %. w;.;.. %.. o-). H. ?. r :s.'?ig 6
.L..
s
,t
.. n g 8 in.>f '.,n'
- J:w. c,.:, u w
'1'p N'TQ 9
q t, % M w & % P n p =. Q N s.:,, q
- . &y
.*g AMb,t,._:-;.gWD. ~ ?. e.,;
%%:b
.t, mw c
m
% n q%p;C:
~. -
ra
' ;;]pu$,w$c$%g.p,WT.qlG@;3n;iyM 0
1Q%wd
( e ?'hk&hl$1bl0$$hf{,&$.p
,pg.A x
- W m 4 - n.r c.
g NSf'W
&q 1
~~
hN
& %P'WMEthh%i; hea $h bh5Nfh N N hM 100X Dp3ft@?d;tp?.5,,;'h'%1,g &.'h' p.mMAsyr 3Sfrc
't N
'M N
%Wu. aGy t. < +q I >,,,,%j+w f@%'hi$w$& i.3.,.m s
,:_~m* ~.w F,y AG.,.ly t y
.a.
M+V.
W,p..q V 'l, ?.kh5 i.
%,$: .'iW9
(/
,,k.ff 'r.,1./ x v Ql gfj.?: R, 4.>gl,
- h., ' +hdYp
,I,E hNON.
1ithg-47.di-6j 3
\\.V.
- J QQyggb{% 9
$f y '
fg m
g 1
g 500X 1500X 2282 276 Figure 11.
Scanning Electron Photomicrographs of Surface of Demineralized Water Control Uniaxial Tensile Specimen Exposed to BWR Environment at 75% of 0.2% Yield Strength 21
NEDC-25159 N W e*.F--T % ?. N J'? y
"?:ih Dy
., 3- @V :i &,}.*iWs $ & O ?s %0 $ W 92 S
y #** &m..< w%d* W ; f.,.s.r:
.,c. w i...%. '-".;. % N W $.3
.6
- 2
.,y L.glJ.'s ' 7 ',...,...,
..3.v.Rh@. 7,%-." 1 F;R'.,40.Tdy v. m,'[~$.
v%. wt,.
. r. w,,
u.;
=.. c. c.
g%-
@5t.%g :-. %,e
.-..cep.. %
, 'n;:.. M.. cr :'.> ' m-s.
- w..
- . ;:y:.~'X. *ni
.e.
s 3
' -e.. -. y
,;g:..~~ q- ;.;u%,. .-
~, ; ~.
a c,.-
. nc.g:.; '.,,. :s.
, v.y
~
m.
y p.e...
v..,.*
...,... s w. n,
,,....*re,.'
...s.
e t
. w,4, af,s g y g gw. s
^'G~
L,.
s%,.f.y~.c~i
... ~.
- . ;.s
...,.'r, s
. ' l -.., og.,1 d* *Q.;.s
, [.,.
'^
Q..
&...?+it.)
.[... *.
'... f. l. i. &.,
.~
k,.%. f
~
Y.. m l. $. m
% e).V. U,,f.;'b'Q. :x. ':~...:~. L -
~
- .c] h'$. -n':'O.>g 5
h,.,.
s.
f-p.".. c p J,,
,; - Q j A.. '. J.
7
.v,,. :.
.n,.
. wy4N
, Wea.,.. u,:s n,p.. ;e..p% %.. z,. y a.. ~.1 L.
. ; u,. <:.,.
?:.
g,,,q:
y 2.
. m. % 4 s
9 emna M M6M W re'"&.$cr3 100X e'
W
.f,f, 5.. m:,;.. [.
,D r',}. Q
%a
, %e.. & =,<
4 ~,,W2.: s., 4*
y
. $ ? V ' w,w % V '^ y.3.'+..r;~E.s.$.
h
?
s 41'M;*
% y' y*1
.iD b}4LL'Q 1,.LJ.~,?,F-h. b s').*y.-
'.. >1', s
'k ' M.,,..
. f. ' t '
- s.
k, g h hh..f.y*%.'. *[g.'N'N s
k y
- ss e
$.y Ap..h
.'s 1
'v$yu mCR;MW.;.:.*;r..y*2.7 M t &.? 4 y
R; e ' '. 5;?<,s ? 1.t:
' f a.
h?W 5.Y:1. }f
's,
~
,W$h p;e;gtt%.pA. p'\\
9f 2,7 Op b
5 b
$ft l'
b-500X 1500X 2282 277 Figure 12.
Scanning Electron Photomicrographs of Surface of NS-1 Uniaxial Tensile Specimen Exposed to BWR Environment at 75% of 0.2%
Yield Strength 22
NEDC-24159 s& p;.4.. ':.n,-mac, h;.. g:;.yw.jp.vey;th.,%m n.g.rg..
- v w.m k,,.,,
- ~-
.., >MyA.m.' n vn.,m,,..
...v. y-, t.
n,..m....,, +,,
- v. ;. ;
~
- r,4..
- o.s.
<y w a
a
%&Kr.yp. :\\": a;.1 mi'Q.'Yl:f *q'*l;w$'V e.t.l f;'x q!.Y k%$dh.'.Q,5b y.' M.. 'D..Q. *($;;;.'rD4e}x*=.
w I'hi.
(A*
- %s
..?
?.'
s 4.)^$. 'y;
.. 3[.'. ~.9dD.
?".; y *,%...f-a y. ?,
.r.
(a*;p'.. e%v.. v..>.s..x ~.- ~-
. +
L,3; ~,
. ?.
_.:',, m..:e.,
.?',; * *a <e g.~. w y,,.. <,.
-p.*
4; s*
' 3 ;.y g;..
- L; ;:,q.y,;
- %.. ',f: s 3,
. n.
- ?!.i g *,.*
s.*
.z t?a s.;Q. ;. ; 'c'; ' '..
2
~
/ i t..s
- ew...,-
.s.
s
,. r,a-<-
c- 'm e..-
~
, +-
p,,; p:,.,,..
2.,
. c.,
c.
. ~;*i~;-
o.',..-
,, py. ; 3, r~.
,s o'
y:..
'.'.;;. d h ?s
~
~
,. n..
. 7
_. n., _..' ;.
....g ',
- 'KT?.T' / l " :
=
k"Je.~rm;e,.
b C,
..a.
..~. ~_ q, Q m.p,-
h#) e *
- ~
^5 q.p r'.. M.e s,:.y,,. T : $. 2 >
5
. ^
k.W-c.,%;,j, *Q.pA.-
....~~*;g'.
~ * :.s p...
- A-g,3.*; '.:. -., '.
,.if,f. M. 2 ~ j =. *..*4 f.,.,.. lr._-%y7, *,'
- m... - w'. -
,a
, -4.i.a.s -
c.
i.
-c p v
.m
. y w _s M.
M.h.,%y k@ hb'h[b,. _.
3 Nk,Qh.
s %'et c~.N d.:'u; M,wb.!Fr.x,>,rik*A'.M.w.'T.%.f%.'Nf~~f 'g ' E
.D 4
'>Mw.2 b,, Q P... " w% 'Wb..
6,-- vy w
$a h
-s
.-Nc e.D-dX 2
100X
, %.h.1.$,;,NNpNk.,.
'W.
p$WMiW..,.M.-6.,w"nMs8i f %
in'e g'7W.sM + : y.wg <
. v r g.r-e. <,
m
-cc h~a.w, e(h,'0kh.f
+w y~p Ta.-:.a),
9m lft W.jp
. u.
.t.
(*N
". 2
%b$b h5 0Y5.?
. ' Y)-+.$
500X 1500X 2282 278 Figure 13.
Scanning Electron Photomicrographs of Surface of Demineralized Water Control Bent Beam Specimen Exposed to BWR Environment at 2% Strain 23
- w 'r'v+
- N(.N.r:*.-@ --?::g,;~,.~~-:: e f,:. f y+.M. ~ we g cx*
p
-u w.
ww; :.y.:x 7.~. ; gnc,2. *+4. -..:n..n. t:.o1, g.y.b...,Qm<<;..-
. c,14 -,
,, s n.< ~M%u 3...
.a...%.::e< 's<e.t
- .yQ.w..sw ~ p<;.
- s...,
.m. r.:, ~; ; Qw,<.. <,,:. 'y. w;?
u=p>:g. :.Q.a...
r
- s
. 3 ;g. v ~v n
s,..~,N,. mp. y * :g.~.
e;:..-
k.g~.
^ ~.
. m.,.,. ~. ?.u ?y.+,.,1 g % q e
.s
- w x r.
..e;
=, m..
. m:e u _.
. x. s. ',,. s '*-f,,*
g e
,C yj 7.**-
.. e rs
, v, e. ?p'.f *....,.,,Y
%?
g'n m,.. ~ :.n...,'l' W
,'+.,g.'.'
e.
a*
s,..
- t **n o
s
..s
- L., :?
.., ::w.
~,, '*
- :..: &.'>y
.~ t: s -
av. w.c 4.'. : S *~, v~ -.s,.
v-:$ % C;,
rn ?.,f .%.. @ :: n -?,0 c;:.~ -l:
o e,i,.Q<,, ~< "wk...,.p ;-A y:.c v; <, 4v,. s, w.;. f'4_f i. A,,;,;%;
4 -?:
.y 8...g,.,
n p"
J, 4%g ;..o
- f g.,r * % v */;%
- . -'
.s N' c DY(($c' ~ hh sh
'NE h* *s;<.4:a.u+w[?,,@%.'7,, *% n;W;;s...,W-.sk:v 9
C 7.
~-
, e-w.mf, :=% nA. A.'x.
u
< ~ vec 'f. R, "~-
WWA#t%'1%.c',9g&s.e.0,-:y' T -i ',,
.. c a,
. w
-24~
, ~. ci
- .'.,. -p2 ':
.,,>,fvs4.i ;.. -. 3 Q.W%
4 f.g.g.s h
n M
4 T. k ' k;* L. N !)'i c M,%. 9 "v. mud 5,$
f., N 4'.drg #. 1 n.:rr. V
-x>fp 5
r w%
YM<
9.Wh.
- D;s'M.w *:?tM.7;cSy*d
~,
SMS.MZll@<'.d)%*,h.g'<f *It'-h' ),e
- A
,,,,/h 3
W$!nMLW3.2WfE&. J2n'*f i'.32:7re sa4L..
100X W
h W.h..,<d@.';,g'['
-1 Q
Q.* s t. * . Y knWt.':, > ~ s.W r... %-7* w ;3f:.s p!;c s f. f.: ,3 .t ~ p(c f.,y m.,,y, 3y.Q k$N$:hJ..u ,A v c. 1 ~
- T ' ? s.h-s.g*fR)%f' N5&*k$.',c ?;(
&Q ... ~. y. e-e.: i, V.,y I; $WW N' I-(3@%-'.e.g,Pr1>J.WT- .p.',)f. ,4< *pA/ ^+ j' .3 . p t + /. b \\*3,$ f/ 4 p.g. oA.~ y.c - .8 "2282 279 = Figure 14. Scanning Electron Photomicrographs of Surface of NS-1 Bent Beam Specimen Exposed to BWR Environment at 2% Strain 24 ':E DC-2 4159 e-s CONTROL SPECIMEN (AS-POLISHED) 250X t NS,1, SPECIMEN (AS-POLISHED) 250X 2282 280 Figure 15. Longitudinal Sections Through Demineralized Water Control and NS-1 Uniaxial Tensile Specimens Exposed to BWR Environment at 125% of 0.2 Yield Strength 25 NEDC-24159 L CONTROL SPECIMEN (AS-POLISHED) 250X r, s_g -.g. ~ NS 1 SPECIMEN (AS-POLISHED) 250X 2282 28I Figure 16. Longitudinal Sections Through Demineralized Water Control and NS-1 Uniaxial Tensile Specimens Exposed to BWR Environment at 100% of 0.2 Yield Strength 26 NEDC-24159 L CONTFIOL SPECIMEN (AS-POLISHED) 250X ) NS.1 SPECIMEN (AS POLISHED) 250X 2282 282 Figure 17. Longitudinal Sections Through Demineralized Water Control and NS-1 Uniaxial Tensile Specimens Exposed to BWR Environment at 75% of 0.2 Yield Strength 27 NEDC-24159 CONTROL SPECIMEN (AS-POLISHED) 250X NS 1 SPECIMcN (AS-POLISHED) 250X 2282 283 Figure 18. Longitudinal Sections Through Demineralized Water Control and NS-1 Bent Beam Specimens Exposed to BWR Environment at 2% Strain 28 NEDC-24159 .$ ? 4 5.- 3 l',q%c \\,Q N .r /g75 9 ,..y p,s,s- ./,, ~ s ./ ps, s./ j // / /> soox Figure 19. Lightly Etched High Magnification Photomicrograph of Tensile Surface of NS-1 Bent Beam Specimen (Note that Intergranular Penetrations Are Filled with Oxides and that Oxide Film is Continuous Over the Specimen Surface) 2282 284 29 ?;EDC-2 4159 th4'
- 5. w
- e f)
.3 ,.7 )E.,, g,, y'il f ,,g '%[IYg t I hfhjk. hf ,.j .s 300X Figure 20. Scanning Electron Photomicrograph of Inside Diameter Surface of Pipe Heat No. 78500 in As-received Condition, Showing Intergranular Attack. 2282 285 30 NEDC-24159 0 i ~~' C_____3 o Figure 21. Typical Uniaxial Tensile Specimen Location in Pipe Mid-wall, with All Gage Section Surfaces Fully Machined a. IDEAL MID-WALL LOCATION, WITH ALL SURFACES FULLY MACHINEO b. OUTSIDE DIAMETER SURFACE LOCATION, WITH POTENTIAL ORIGINAL PIPE SURFACES ON THE UPPER EDGES x1 c. INSIDE DIAMETER SURFACE LOCATION, WITH POTENTIAL ORIGINAL PIPE SURFACE ON THE LOWER FACE OF THE SPECIMEN 2282 286 Figure 22. Idealized Possible Locations of Bent Beam Specimens in Pipe Wall 31 NEDC-24159 6. REFERENCES 1. Techniel Study for the Chemical Cleaning of Dresden 1, Dow Chemical Company, DNS-D1-016, June 15, 1977 2. W. L. Walker, Correlation Analyses of Mechanical Properties, General Intergranular Corrosion, and Intergranular Stress Corrosion Cracking Data from Hultiple Heats of Type 304 Stainless Steel, NEDM-13347, July 1973 3. W. L. Walker, Intergranular Corrosion Tests of Sensitized Type 304 Stainless Steel in Dow NS-1, and Stress Corrosion Cracking Tests of Type 304 Stainless Steel and Carbon and Low Alloy Steels in Dow Copper Rinse Solution, NEDC-24143, Septena;er 1978 2282 287 32 NEDC-24159 INTERNAL DISTRIBUTION Name M/C L. D. Ans tine V04 R. L. Cowan 407 W. R. DeHollander 110 J. S. Cay 888 B. M. Gordon 138 G. M. Gordon 138 R. B. Hamilton 853 J. H. Holloway 585 J. C. LeMaire 138 R. A. Proebstle 146 W. H. Reas V04 C. P. Ruiz V04 W. L. Walker (5) 407 D. E. Wax V17 NED Library (5) 328 VNC Library V01 EXTERNAL DISTRIBUTION Name M/C J. C. Blumgren CECO T. D. Boyce DNS C. F. Cheng ANL J. S. Graves CECO D. H. Harmer DNS W. I. Kiedaisch CECO T. Y. Moon DNS G. L. Redman CECO R. W. Staehle OSU R. Taminga CECO G. P. Wagner CECO J. L. White (55) CECO 2282 288 33/34 4 GENER AL h ELECTRIC 2282 289