Volume 42, Issue 4 (July 1997)
The Surface Analysis of Copper Arc Beads—A Critical Review
The chemical composition of arc beads has been purported to reflect the local atmospheric conditions at the precise moment when the arc occurs. It has further been claimed that Auger analyses, taken from beneath the surface contamination layers of an arc bead, can be used to distinguish whether the arcing was the cause of a fire. The hypothesis is that because atmospheric gases are trapped in the arc bead when it solidifies, the concentrations of gases inside the bead will reflect ambient conditions when the arc causes the fire, but rich concentrations of combustion gases when it does not. A review of the literature on the solubility of gases in liquid copper indicates that there is no scientific justification for this hypothesis.