Open AccessTENSILE PROPERTIES OF PYROLYTIC GRAPHITE TO 5000 F
Author(s) -
W.V. Kotlensky,
H. E. Martens
Publication year - 1961
Language(s) - English
Resource type - Reports
DOI - 10.2172/4001222
Subject(s) - ultimate tensile strength , materials science , pyrolytic carbon , graphite , elongation , composite material , microstructure , deformation (meteorology) , tensile testing , atmospheric temperature range , helium , atomic physics , chemistry , physics , pyrolysis , thermodynamics , organic chemistry
Tensile properties of pyrolytic graphite were measured parallel to the basal planes from room temperature to 5000 deg F. The gage section of the test specimen was 0.06 by 0.10 in. in cross section and3/4-in. long. The specimens were heated in a helium atmosphere by an external graphite heater and were tested at a strain rate of approx 2 x 10/sup -//sup 4/ in./in./sec. Tensile strengths at room temperatare varied from 6,000 to 19,000 psi with elongations of less thsn 1%. At 3000 deg F the strength and elongation were approximately the same as at room temperature. At 4000 deg F there was a very slight increase in the strength and elongation. At 4500 deg F tensile strengths to 35,000 psi and elongations up to 3%, and at 5000"F tensile strengths of 64,000 psi and elongations greater than 70% were measured. At 4500 deg F and above load-deformation curves were recorded. Microstructure and x-ray diffraction patterns showed that marked structural changes accompsny deformation at 5000 deg F. Large changes in room-temperature dimensions, parallel and perpendicular to the basal planes, were measured after heating, with no load, to temperatures in this same range. (auth