Abstract
The objective of the investigation was to determine the cause of wide variations (factor of 5) observed in the bulk thermal expansion of the polycrystalline graphites: ATJ‐S, AXF‐5Q, mesophase and isostatically pressed. An attempt to rationalize this spectrum on the basis of lattice thermal expansion was unsuccessful because of the relatively small differences in that lattice expansion. Addition of boron to the isostatically pressed graphite reduced the thermal expansion in the c‐direction by approximately 30%. The very low thermal expansion coefficient of ATJ‐S as compared to AXF‐5Q and the mesophase‐based graphite can be explained by the existence of very small microcracks between the layer planes in the ATJ‐S filler particles. In the AXF‐5Q and mesophase‐based graphites, very little micro‐cracking could be distinguished. The qualitative theory of Mrozowski and the more quantitative model of Buessem were examined. It was found that the results are essentially in agreement with Buessem's model. The isost...
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
