Accession Number:

AD0270254

Title:

THE YOUNG'S MODULUS AND INTERNAL FRICTION OF POLYCRYSTALLINE MGO AT ROOM TEMPERATURE

Descriptive Note:

Corporate Author:

NEW YORK STATE COLL OF CERAMICS ALFRED

Personal Author(s):

Report Date:

1961-09-01

Pagination or Media Count:

1.0

Abstract:

Hot pressing method was used to prepare polycrystalline MgO from several starting powders, which behaved distinctly from each other. A direct relationship between the activity of the powder and its compressibility was found. As the density of the specimen increased the Youngs modulus increased linearly, whereas the internal friction decreased. It was found that t e internal friction was inversely proportional to the square of t e grain diameter. Mg specimen of the same density, but from different origin may not necessarily have the same Y ung o ulus r internal riction values t e e differences may be attributed to the presence of foreign atoms. A UTHORAD - AD-270 255Div. 25, 14U TISTMGEC New York tate Coll. of Ceramics, Alfred U. ULTRAVIOLET, VISIBLE, AND INFRARED TRANSMISSION IN MAGNESIA, by Rino Hanna and W. B. Cran all. 7 Jan 62, 6p. illus. tables, 9 refs. Rept. no. 2 Grant no. DA-ORD-31-124-60-G58 AROD rept. no. 28912 Unclassified report No automatic release to Foreign Nationals. DESCRIPTORS Ceramic materials, Mag nesium compounds, Oxides, Single crystals, Crystals, Optics, Light transmission, Ultra violet radiation, Infrared radiation, Thick ness. Optical absorption measurements were made rom 0.34 to 13 microns on single crystal and polycrystalline MgO. The polycrystalline samples were prepared by hot pressing to theoretical density. Two different types of this polycrystalline MgO are described, both types being translucent in the visible region. Two largeABSORPTION BANDS WERE OBSERVED IN BOTH THE SINGLE CRYSTAL AND POLYCRYSTALLINE MATERIAL THE FIRST AT ABOUT 11 MICRONS AND THE SECON AT A OUT 12.7 MICRONS. Author

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Distribution Statement:

APPROVED FOR PUBLIC RELEASE