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Description: A compilation is given of corrosion data for approximates 570 samples that were exposed prior to Dec. 31, 1961, to flowing sodium in six sodium mass transfer test loops. The loops and samples comprised 316 stainless steel, 21/4 Cr--1 Mo steel, and/or 5 Cr-- 1/2 Mo-- 1/2 Ti steel. Analysis reports are also presented for all the test runs reported. (D.L.C.)
Date: May 1, 1962
Partner: UNT Libraries Government Documents Department


Description: A steam generator, wherein the boiler, steam drum, and superheater are integrated into one single unit, requires the welding of a transition joint between the 2 1/4% Cr-1% Mo steel of the steam drum and the type 316 stainless steel of the superheater. A practicable procedure was developed for the welding of this transition joint and the properties of the weld were evaluated by mechanical testing and metallurgical evaluation. After evaluating the technical aspects of the project and their relation to the fabrication of the generator, it was considered desirable to overlay the welding edge of the 2 1/4% Cr-1% Mo steel with a suitable austenitic weld metul which would subsequently be welded to the type 316 stainless steel of the superheater. Austenitic stainless steel and high-nickel alloy weld metals were evaluated for the overlay; whereas only austenitic stainless steel weld metals were evaluated for the final weld joining the components. It was concluded that type 309 stainless steel weld metal deposited automatically by the submergedarc process is completely satisfactory for cladding the 2 1/4% Cr-1% Mo base metal and for making the final transition weld joining the steam drum and superheater sections of the generator. Supplementary mechanical tests, metallographic examinations, and hardness surveys further attested to the adequacy of the quality of the transition joint resulting from the procedures developed by this program. A detailed fabrication and thermal treatment specification is included for the welding of a transition joint between
Date: August 15, 1960
Partner: UNT Libraries Government Documents Department

Tensile and Charpy impact properties of irradiated reduced-activation ferritic steels

Description: Tensile tests were conducted on 8 reduced-activation Cr-W steels after irradiation to 15-17 and 26-29 dpa, and Charpy impact tests were conducted on steels irradiated to 26-29 dpa. Irradiation was in Fast Flux Test Facility at 365 C on steels containing 2.25-12% Cr, varying amounts of W, V, and Ta, and 0.1%C. Previously, tensile specimens were irradiated to 6-8 dpa and Charpy specimens to 6-8, 15- 17, and 20-24 dpa. Tensile and Charpy specimens were also thermally aged to 20,000 h at 365 C. Thermal aging had little effect on tensile properties or ductile-brittle transition temperature (DBTT), but several steels showed a slight increase in upper-shelf energy (USE). After 7 dpa, strength increased (hardened) and then remained relatively unchanged through 26-29 dpa (ie, strength saturated with fluence). Post-irradiation Charpy impact tests after 26-29 dpa showed that the loss of impact toughness (increased DBTT, decreased USE) remained relatively unchanged from the values after 20-24 dpa, which had been relatively unchanged from the earlier irradiations. As before, the two 9Cr steels had the most irradiation resistance.
Date: October 1, 1996
Creator: Klueh, R.L. & Alexander, D.J.
Partner: UNT Libraries Government Documents Department

Flow lines and microscopic elemental inhomogeneities in austenitic stainless steels

Description: Flow lines in mechanically formed austenitic stainless steels are known to influence fracture behavior. Enhancement of flow lines by chemical etching is evidence of elemental inhomogeneity. This paper presents the results of electron microprobe analyses to determine the nature of flow lines in three austenitic stainless steels: 21Cr-6Ni-9Mn, 304L, and 19Ni-18Cr.
Date: January 1, 1982
Creator: Mosley, Jr, W C
Partner: UNT Libraries Government Documents Department

Microstructural Stability and Oxidation Resistance of 9-12 Chromium Steels at Elevated Temperatures

Description: Various martensitic 9-12 Cr steels are utilized currently in fossil fuel powered energy plants for their good elevated temperature properties such as creep strength, steam side oxidation resistance, fire side corrosion resistance, and thermal fatigue resistance. Need for further improvements on the properties of 9-12 Cr steels for higher temperature (>600oC) use is driven by the environmental concerns (i.e., improve efficiency to reduce emissions and fossil fuel consumption). In this paper, we will discuss the results of the research done to explore new subsitutional solute solution and precipitate hardening mechanisms for improved strength of 9-12 Cr martensitic steels. Stability of the phases present in the steels will be evaluated for various temperature and time exposures. A comparison of microstructural properties of the experimental steels and commercial steels will also be presented. <br><br> The influence of a Ce surface treatment on oxidation behavior of a commercial (P91) and several experimental steels containing 9 to 12 weight percent Cr was examined at 650ºC in flowing dry and moist air. The oxidation behavior of all the alloys without the Ce modification was significantly degraded by the presence of moisture in the air during testing. For instance the weight gain for P91 was two orders of magnitude greater in moist air than in dry air. This was accompanied by a change in oxide scale from the formation of Cr-based scales in dry air to the formation of Fe-based scales in moist air. The Ce surface treatment was very effective in improving the oxidation resistance of the experimental steels in both moist and dry air. For instance, after exposure to moist air at 650ºC for 2000 hours, an experimental alloy with the cerium surface modification had a weight gain three orders of magnitude lower than the alloy without the Ce modification and two orders of ...
Date: May 1, 2006
Creator: Dogan, O.N.; Alman, D.E.; Jablonski, P.D. & Hawk, J.A.
Partner: UNT Libraries Government Documents Department


Description: The preliminary work done by Westinghouse on properties of materials suitable for the in-pile testing facility was reviewed. Information was collected on a selected list of promising materials in the following classificrtions: alloy steels, chromium steels, precipitation-hardening stainless steels, and superalloys. On the basis of the information obtained from Westinghouse, from the literature survey, from Battelle files, and from visits to producers, it is recommended that Phase II of the program be confined to Inconel X hot rolled and aged, AM-350 subzero cooled and tempered, and Discaloy solution treated and aged. (auth)
Date: September 16, 1957
Creator: Simmons, W.F.; Boyd, W.K.; Sopher, R.P. & Lyon, F.H.
Partner: UNT Libraries Government Documents Department

Analytical description of the effects of melting practice and heat treatment on the creep properties of a 2 1/4 Cr-1 Mo steel

Description: 2/sup 1///sub 4/ Cr-1 Mo steel is used worldwide as an elevated-temperature structural material, particularly in steam generation systems. Since this material is often used at service temperatures up to 600/sup 0/C, successful design requires a consideration of its creep properties. Unfortunately, the development of an analytical description of the creep behavior of 2/sup 1///sub 4/ Cr-1 Mo steel is complicated by two phenomena. First, the creep strength of this material is quite sensitive to heat treatment. Second, this material tends to exhibit nonclassical creep under some conditions. In addition, especially in nuclear applications, the material used may be air-melted, vacuum-arc remelted (VAR), or electroslag remelted (ESR). Available creep data from air-melted, VAR, and ESR material have been analyzed. Heat treatments included both annealed and isothermally annealed, with and without a subsequent ''postweld'' heat treatment. It has been found that the elevated-temperature ultimate tensile strength (UTS) is a useful indicator of creep strength for a given heat of material regardless of melting practice or heat treatment. Meanwhile, the nonclassical creep behavior has been attributed to a change in creep mechanism which has been mathematically modeled.
Date: January 1, 1977
Creator: Booker, M.K.
Partner: UNT Libraries Government Documents Department

Austenitizing and microstructure of a HT-9 steel

Description: The effects of austenitizing temperatures and times on the microstructure of a 12Cr-1Mo-V-W steel are reported. Austenitizing temperatures covering the range of 900 to 1225/sup 0/C and times of 30 minutes to 100 hours were used. Equilibrium microstructures were difficult to obtain because delta ferrite initially present in the steel resists dissolution during austenitizing. 10 figures.
Date: January 1, 1983
Creator: Wilcox, R.C. & Chin, B.A.
Partner: UNT Libraries Government Documents Department

Thermal aging of annealed 2 1/4 Cr-1 Mo steel

Description: Four commercially annealed tubing heats of 2/sup 1///sub 4/ Cr-1 Mo steel were aged at 454, 510, and 566/sup 0/C for times up to 20,000 hr. Tensile tests were made at room temperature and at the aging temperature on specimens from each heat for each aging condition. Thermal aging significantly affected the strength, the effect being greatest for tests at the aging temperature. The amount and magnitude of the strength changes varied from one heat to the other. After aging for 20,000 hr at 454 and 510/sup 0/C the strength of one heat increased. However, the other three heats showed yield strength and ultimate tensile strength decreases of up to 40%, the maximum effect occurring at 566/sup 0/C. The precipitation processes that give rise to the strength changes have been discussed.
Date: January 1, 1977
Creator: Klueh, R.L.
Partner: UNT Libraries Government Documents Department

Development of automated welding processes for field fabrication of thick-walled pressure vessels: electron beam method. Fourth quarterly report, July 1--September 30, 1978

Description: This report is the fourth quarterly report of a project to develop and demonstrate an electron beam welding procedure for welding 8'' thick SA 387 Grade 22 Class 2 (2-1/4 Cr--1 Mo) steel. Due to the late arrival of the steel to be used in this project, a six month extension in the completion date has been made. Work is in progress for developing 4-1/2'' deep partial penetration electron beam welding procedures. A total of 257 welds have been made to date. Several defects have been encountered and successfully eliminated. The occurrence of a necklace defect, which has been shown to be a cold shut resulting from improper solidification, has not yet been eliminated. It has been observed that the beam oscillation pattern is influential on the behavior of the weld cavity during welding. In the vertical welding position, it has been determined that the use of a welding shoe is required.
Date: January 1, 1978
Creator: Weber, C.M.
Partner: UNT Libraries Government Documents Department