DIRECT MEASUREMENT OF THE DENSITY OF CONNECTED CARBON BONDING IN GRAPHITE
AND CARBON SOLID STATE COMPACTS FOR STRENGTH
MEASUREMENT OF BONDING IN IRREGULAR STRUCTURES
In rough and irregular graphite and carbon based solids,
it is possible to determine the physical integrity by measuring the local
solid’s electrical conductivity. By applying multi frequency, inverse eddy
current analysis to measurements over a wide frequency range, it is possible
to profile the strength of graphite and carbon structures while measuring
the electrical connectivity at depth in the material. The technique
allows one to remove the variance in probe height and isolate the internal
conductivity data when characterizing the bonding.
Defect detection is also possible for inclusion and
fracture detection which produce responses characteristic of their depth
within the material.
Grain texturing anisotropy can be separated from
conductivity variations affected by low density and poor material
bonding with a probe orthogonal to forming direction.
Interior conductivity variation in a warped
2 inch thick by 20” long graphite plate scanned over 12” span, sampling
.75” depth, with a three frequency measurement on the Process Monitor IV.
