High-Temperature Gaseous Corrosion of Zircaloy

High-Temperature Gaseous Corrosion of Zircaloy 2 -A. H. Roebuck 

Samples of Zircaloy 2 were exposed to high-temperature atmospheres of superheated steam, dry air, and moist air to study the corrosion behavior which might occur if coolant were lost from a water-cooled and moderated reactor. 

Tests were carried out in heated quartz tubes, 7/8 in. diameter. Thermocouples, adjacent to the sample, were used to control the temperature. The dry-air test was made with the tube open to the atmosphere. Moist air was provided by passing air through a sintered glass bubbler filled with water. The air was passed through the bubbler and over the heated sample in the quartz tube at a rate of about 30 ml per minute. A 

The results on the Zircaloy 2 tests are given in Table XVI the samples are pictured in Figs. 70 and 71. The rate of weight gain under the various atmospheric conditions is shown in Figs. 72 and 73. 

One test was run on a sample from billet No. 1X082 in dry air for 6 hr in such a way as to simulate a heating-up and cooling-down period. The temperature of this test followed the plot shown in Fig. 74 and reached a meucimum of 1670F. The sample developed a moderately thick, buff-colored powdery oxide and showed a weight gain of 23.05 mg/cm for the test [2,770 mg/(cm )(mo)]. 

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