Thermal Expansion of Polycrystalline Graphite

Publisher Website
Google Scholar
Abstract
Thermal expansion characteristics of a group of polycrystalline graphites have been measured to 2400°C by a method which permits acquisition of meaningful expansion data without resorting to reference standards. Direct measurements on specimens while in the furnace were accomplished by using two 8‐in. focal length Gaertner optical micrometers. Thermal expansion behavior is discussed in relation to orientation, impurity, degree of crystallinity, and grain size. Specimens were heated from room temperature to 2400°C, then cooled to room temperature, taking measurements of thermal expansion throughout both heating and cooling cycles. The existence of hysteresis is observed and discussed.