Electromagnetic Excitation of Coaxially-Coiled Constantan Wires by High-Power, High-Voltage, Microsecond Pulses
Authors: Celani Francesco , Spallone A. , Lorenzetti C. , Purchi E. , Fiorilla S. , Cupellini S. , Nakamura M. , Cerreoni P. , Burri R. , Boccanera P. , Marano E.F. , Vassallo G. , Gamberale L. 
Published: December 2024

This paper is mostly based on our presentation given at the 23rd International Conference on Condensed Matter Nuclear Science (ICCF23) held at Xiamen University (XMU)-PRC on June 9-11, 2021. Upon the suggestion of the Conference Organizers, we added a detailed explanation of our procedures; moreover, we included the latest results and data from our recently published papers. In the framework of LENR-AHE (Low Energy Nuclear Reaction - Anomalous Heat Effects) studies, since 2021, we have been focused on innovative, low-cost materials instead of the usual, precious metal palladium. We found that the Cu-Ni alloy, known as Constantan (also used for J-type thermocouple construction), has the peculiarity of being able to easily dissociate H2 (or D2) from molecular to an atomic state. While the catalytic feature appears at a rather low temperature (150 ◦C), Constantan is also able to store atomic hydrogen within its lattice and/or at surfaces, up to temperature of 700-800 ◦C, and in a wide range of pressures. Thanks to our long experience (since 1994) with wires, we designed various experiments that take advantage of such specific shapes, namely in terms of electromigration of absorbed and adsorbed H, under a suitable longitudinal electric field (0.4-2.5 V/cm), DC and/or pulsed. In 1995 we got noticeable results using Pd wires in electrolytic environments (D2O) at mild temperatures (40-60 ◦C). Later on, in some experiments, we used even gaseous environments at high temperatures (up to 700-800 ◦C). The main problem of Pd was its large brittleness after H or D absorption. Moreover, we experimentally reconfirmed that one of the key conditions to induce AHE is the “flux” of H moving inside its lattice (longitudinal) or through the surface (transversal). Pioneers of transversal flux were G. C. Fralick-NASA [1]; M. McKubre-SRI [2]; Y. Iwamura-Mitsubishi [3], [4], [5]; Y. Arata-Osaka Univ [6]; F. Celani-INFN [7]. We focused mainly on longitudinal flux (following also the theoretical models developed by G. Preparata-Milan Univ. [8], although some of our unconventional electrolytic experiments (1995-1998) had both. In any case, apart from the initial state (the situation of intrinsic hydrogen concentration gradients), the flux needs external energy to be continuously activated. Based on our own experiences since April 1989, AHE are due to non-equilibrium conditions, i.e., they need continuous stimulation, usually energy consuming, apart from some specific (but delicate) geometric set-ups (such as the Capuchin knot, which we began testing in 2018, in some of our geometric arrangements where local thermal gradients were extremely large: > 100 ◦C/mm). Recently, we developed an unconventional geometry of the electrode we aimed to use, and at almost the same time, longitudinal and transversal flux at high temperatures in gaseous environments: our goal was to minimize extra energy added, to maximize the AHE and keep it operative for as long as possible. We report here on procedures to enable flux by high power electric pulsing with both related problematics and peculiar advantages, some unexpected. The core of the reactor is arranged as a reversed coaxial coil with inner electrode made by a Fe tube, which we described beginning in 2019 at ICCF22.