The role of superabundant vacancy delta to delta prime transformation in stopping Fleischmann-Pons heat effect in palladium-deuterium

Abstract

A calorimeter, designed for electrolysis of Pd in heavy water, capable of measuring heat and power output with a precision of ± 0.5%, was used to determine changes in output during a compulsory quick-drop in temperature. The change in temperature was forced on the electrolysis cell while it was producing nuclear energy at excess power levels of 240 W/cm3 and after producing a continuous excess heat amount of 150 MJ/cm3 (14 000 eV/atom of Pd). The temperature change (from 82.5 °C to ∼0 °C) resulted in a total loss of excess power (nuclear power) and indicates the regions of the microstructure that were ordered superabundant vacancy (SAV) phase transformed from δ to the ordered superabundant vacancy phase δ′. The δ phase is responsible for producing excess heat and power while the δ′ phase produces no excess heat or power. Deuterium in the δ phase occupies the octahedral sites but occupies the tetrahedral sites in the δ′ phase. In either case, δ and δ′ are minor phases with volume fractions in the two-phase microstructure of approximately 0.03 and 5.0 percent for δ and δ′, respectively. This evidence of termination of excess power supports previous indications in the literature of such a transformation.