141. A critical examination of the flexural test for graphites

✍ Scribed by G.F Gillis; C.D Pears

• Publisher: Elsevier Science
• Year: 1965
• Tongue: English
• Weight: 142 KB
• Volume: 3
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(65)90207-1

✦ Synopsis

The variations in several thermal and mechanical properties were examined for a large cylinder of CFZ graphite and several small cylinders of ATJ graphite. These property variations were correlated with bulk density, location in the ingot, orientation and in some cases, flaw occurrence as observed by photomicrographs. From a statistical analysis of the data, the maximum uncertainty ranges for the different properties were determined and divided into uncertainty intervals resulting from (1) equipment errors, (2) material variations, and (3) other causes. The variation in some properties showed a definite correlation with the original location of the specimen in the ingot and with density. Ultimate tensile strength, ultimate flexural strength, and thermal expansion were typical of these. Other properties such as electrical resistivity exhibited some trend but the variation was difficult to separate from the uncertainty of the measurement. The effects of other parameters such as impurities, cracks and other inhomogeneities on physical properties are discussed. Suggestions are made for further study to determine the effect of the property variations on design parameters and material requirements.