EVALUATION OF TGA AS A QUALITY ASSURANCE TOOL FOR SURFACEMODIFIED ZIRCOLOY-4

[摘要] Thermogravimetric analysis (TGA) and coupled Mass Spectroscopy (MS) were evaluated to determine their suitability as a quality assurance tool for surface modified nickel plated zircaloy-4 liner tubes. Samples with 0, 0.1, 0.2, 0.3, and 0.4 mils of heat treated nickel plate were tested at 330, 370, and 400 C. Not all of the samples exhibited the expected typical parabolic shaped oxidation curve. The measured weight change was consistent for the as received and 0.2 mil and the 0.4 mil surface modified samples. None of the samples were tested under aggressive enough conditions to consume the surface modified materials during the test duration. Use of the Mass Spectrometer in conjunction with the TGA did not produce valuable data and was only used for the 400 C test series; however, the TGA was valuable. The 0.1 and 0.3 mil surface modified Zr-4 samples exhibited thru surface modified layer cracks which could account for the variation in oxidation behavior. TGA tests for periods up to six hours appear viable as a method to ascertain oxidation behavior for consistent results. Additional testing of samples with known variations in surface modified layer thickness and quality is recommended as part of the QA acceptance testing.

[发布日期] 2009-09-21

[学科分类] 材料科学（综合）

[关键词] EVALUATION;LINERS;MASS SPECTROMETERS;MASS SPECTROSCOPY;NICKEL;OXIDATION;PLATES;QUALITY ASSURANCE;TESTING;THERMAL GRAVIMETRIC ANALYSIS;THICKNESS;ZIRCALOY 4