Indentation creep of superelastic hard carbon

Abstract

Instrumented indentation methods have been used to study the effect of the loading rate and holding time at different maximum loads on the indentation characteristics of superelastic hard carbon particles reinforcing metal matrix composite materials. The properties of the carbon particles prepared in fullerite-metal powder mixtures by high-pressure synthesis substantially differ as a function of synthesis parameters (P, T) and the initial fullerite characteristics (C60 in crystalline or amorphous state). The indentation creep C IT decreases with increasing F max (500-2000 mN) and increases with holding time (60-600 s). The harder carbon particles formed from amorphous fullerite are characterized by higher indentation creep CIT and deeper penetration at constant load. Such creep behavior correlates with different elastic recovery characteristics of the particles upon indentation.

Rotational Dynamics of Fullerenes in the Molecular Crystal of Fullerite

“…[ 1 ] A whole group of both theoretical and experimental works is directly focused on revealing the effect of increasing the hardness of fullerene‐containing materials. [ 2–12 ]…”

“…[ 28 ] It should be noted that changes in the initial characteristics of fullerite significantly affect the properties of synthesized carbon particles. [ 10 ]…”

“…[1] A whole group of both theoretical and experimental works is directly focused on revealing the effect of increasing the hardness of fullerenecontaining materials. [2][3][4][5][6][7][8][9][10][11][12] Under normal conditions, C 60 molecules are located at the sites of the crystal lattice of the fullerite crystal and interact with each other through the weak van der Waals forces. Under these conditions, they have a relatively low hardness.…”

“…[28] It should be noted that changes in the initial characteristics of fullerite significantly affect the properties of synthesized carbon particles. [10] The quantum mechanical approach can be used to study gyroscopic effects. [29] However, this approach has much more grounds for application in the region of low temperatures, which determine the state of the material.…”