RESEARCH ON ZIRCONIUM ALLOYS WITH NIOBIUM AND/OR SILICON WITH A VIEW TO THEIR USE AS CLADDING MATERIAL IN WATER-COOLED NUCLEAR REACTORS. Quarterly Report No. 4, January 1, 1961-March 31, 1961

Technical Report · Mon Apr 17 00:00:00 EST 1961

OSTI ID:4802456

Anderko, K; Jung-Koenig, W; Richter, H; Winciers, P; Zwicker, U; Sagel, K; Zimmermann, R

Constitution tests on the Zr-Nb state system were pursued, and it was found that even in iodide-zirconiumbased alloys the monotectoidal reaction beta / sub Zr in equilibrium alpha /sub Zr/ + beta /sub Nb/ does not occur at constant temperature. As the result of an unavoidable oxygen content, a three- phase field also occurs here in which the monotectoidal reaction extends over a large temperature interval. The monotectoidal composition was established at l9% Nb. A process to determine the solubility of alpha-Zr for niobium below 570 deg C is described. The alpha-zirconium solid solution does not age-harden. The comparative corrosion tests conducted during the fourth quarter showed that heat- treatment below the mono tectoidal temperature brings about optimum resistance. The effect of heat-treatment is highest in pressurized water at 350 deg C, but more limited in high-temperature steam. The presence of tin is favorable in pressurized water, unfavorable in high-temperature steam. Addition of palladium has an unfavorable effect. Tests in circulating steam at normal pressure give results similar to tests in high-pressure steam. Zircaloy-2 and ZrNb3Snl tubes were fabricated for thermal cycling elongation tests. The first tests carried out showed that thermal cycling brings about a certain contraction of the extrusion-hardened tubes. Tensile tests and micro-tests at room and higher temperatures were performed on the Zircaloy-2, ZrNb2, and ZrNb3Snl alloys envisaged for fatigue testing. Current fatigue tests such alloys extended over periods of 500 to 2000 hours. According to the results so far obtained, alloys containing niobium would appear to have a higher fatigue resistance than Zircaloy- 2. Even afier heat-treatment at 575 deg C, which is unfavorable for fatigue resistance, though favorable for corrosion resistance. The ZrNb3Snl alloy proved to be appreciably superior to Zircaloy-2. (auth)

• Research Organization: Metallgesellschaft A.G., Frankfurt am Main
• DOE Contract Number: 009-60-4RDA
• NSA Number: NSA-16-010526
• OSTI ID: 4802456
• Report Number(s): EURAEC-86
• Resource Relation: Other Information: Work Performed under United States-Euratom Joint Research and Development Program. Orig. Receipt Date: 31-DEC-62
• Country of Publication: United States
• Language: English

Related Subjects

METALS, CERAMICS, AND OTHER MATERIALS
ALLOTROPY
CORROSION
CORROSION PROTECTION
EFFICIENCY
EXTRUSION
FABRICATION
FATIGUE
FUEL CANS
HEAT TREATMENTS
HIGH TEMPERATURE
IODIDES
MATERIALS TESTING
MONOTECTOIDS
NIOBIUM
NIOBIUM ALLOYS
OXYGEN
PALLADIUM ALLOYS
PHASE DIAGRAMS
PRESSURE
REACTORS
SILICIDES
SOLID SOLUTIONS
SOLUBILITY
STEAM
TEMPERATURE
TEMPERING
TENSILE PROPERTIES
TIN
TIN ALLOYS
TUBES
USES
WATER
WATER COOLANT
ZIRCALOY
ZIRCONIUM
ZIRCONIUM ALLOYS
ZIRCONIUM-ALPHA
ZIRCONIUM-BETA