Accession Number : AD0721322

Title :   An Experimental Study of the Heat Generated during Cyclic Deformations of Glass-Epoxy Composites.

Descriptive Note : Technical rept.,

Corporate Author : PRINCETON UNIV N J DEPT OF AEROSPACE AND MECHANICAL SCIENCES

Personal Author(s) : Segol,Genevieve ; Tauchert,T. R.

Report Date : DEC 1970

Pagination or Media Count : 116

Abstract : Data are presented which show the effect of frequency and strain amplitude on glass- fiber reinforced plastic specimens subjected to torsional oscillations. The first part of this work is concerned with hysteresis loops recorded at frequencies of 120, 210, and 300 cpm and angles of twist equal to 10, 15, and 20 degrees. Data corresponding to various ambient temperatures were also obtained. The second part deals with steady-state experiments, in which the specimen was oscillated until the surface temperature reached a steady-state value. The temperature and stress histories were recorded simultaneously. The results presented and discussed show that for certain angles of twist and certain frequencies of oscillation the material softens considerably. In these cases a large temperature rise occurs and the stress decreases suddenly while discoloration and delamination appear at the surface of the specimen. It is clear from this research that when glass-epoxy composite materials are subjected to cyclic tests, the phenomenon of heat generation can be very important and depends on the strain amplitude and on the frequency of oscillation. (Author, modified-PL)

Descriptors :   (*REINFORCED PLASTICS, HEATING), GLASS TEXTILES, EPOXY RESINS, THERMAL ANALYSIS, DEFORMATION, LOADS(FORCES)

Subject Categories : Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE