Accession Number : AD0638336

Title :   THE INFLUENCE OF CONSTITUTION AND MICROSTRUCTURE ON THE TRANSVERSE STRENGTH OF A CRYSTALLIZED GLASS.

Descriptive Note : Technical memorandum.

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK ORDNANCE RESEARCH LAB

Personal Author(s) : Davis,R. F.

Report Date : 03 AUG 1966

Pagination or Media Count : 90

Abstract : The thermal expansion behavior and abraded and unabraded transverse strengths of a glass, nucleated glass, and 15%, 30% and 50% crystalline glass-ceramic were correlated with the constitution and microstructure of these specimens. X-ray diffraction patterns revealed that the crystalline phases present were those of diopside and beta-eucryptite in varying amounts depending on the percentage of crystallization. The bulk thermal expansion coefficients of the unnucleated, nucleated, and 15% crystalline samples were of approximately the same value because they were determined primarily by the expansion characteristics of the glass or continuous glass matrix; whereas, the expansion coefficients of the 30% and 50% crystalline specimens decreased with increasing crystallinity because they were determined by (1) the positive expansion characteristics of the glass and diopside crystals and (2) the dominating negative bulk expansion coefficient of beta-eucryptite.

Descriptors :   (*GLASS, FLEXURAL STRENGTH), MICROSTRUCTURE, THERMAL EXPANSION, NUCLEATION, CRYSTALLIZATION, DEFECTS(MATERIALS), DIFFERENTIAL THERMAL ANALYSIS, ELECTRON MICROSCOPY, BENDING, STATISTICAL ANALYSIS

Subject Categories : Ceramics, Refractories and Glass
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE