An object is to provide a graphite-copper composite electrode material that is capable of reducing electrode wear to a practically usable level and to provide an electrical discharge machining electrode using the material. A graphite-copper composite electrode material includes a substrate comprising a graphite material and having pores, and copper impregnated in the pores of the substrate, the electrode material having an electrical resistivity of 2.5 m or less, preferably 1.5 m or less, more preferably 1.0 m or less. It is desirable that the substrate comprising the graphite material have an anisotropy ratio of 1.2 or less. It is desirable that an impregnation rate of the copper in the electrode material is 13% or greater. It is desirable that the substrate comprising the graphite material have a bulk density of from 1.40 Mg/m.sup.3 to 1.85 Mg/m.sup.3.

Methods including preparing a mixture including a binder composition containing at least one binder and at least one mineral filler, and curing the mixture to produce a material having improved electrical conductivity at 20 C., where at least 20% by weight of the at least one mineral filler is iron-containing slag.

The present application relates to an electrically conductive asphalt mastic (ECAM) composition that includes an asphalt binder, a mineral filler, and a plurality of conductive carbon microfibers, between 3 and 12 mm in length, which are the sole source of electrical conductivity in the ECAM composition where the conductive carbon microfibers and the mineral filler are dispersed in the asphalt binder, and wherein said conductive carbon microfibers are present in the ECAM composition in an amount of less than 2.00% of total volume of the ECAM composition. The application further relates to an electrically conductive asphalt concrete (ECAC) composition that includes an asphalt binder, a mineral filler, an aggregate, and a plurality of conductive carbon microfibers, where the conductive carbon microfibers are the sole source of electrical conductivity in the electrically conductive asphalt concrete composition.

An electrical filter is disclosed. The electrical filter can include a conductive concrete structure including at least one of a conductive carbon material, a magnetic material, or a conductive metallic material. The conductive concrete structure is characterized by an electrical conductivity greater than 0.5 siemens per meter. The electrical filter also includes at least one electrical cable disposed within the conductive concrete structure. The at least one electrical cable includes an input to receive an electrical signal and an output to output an attenuated electrical signal.

An electromagnetic interference (EMI) resistant cementitious ink comprising a hydraulic cement, calcium carbonate, silica sand, taconite material, and a conductive material. A ratio of the silica sand to the taconite material is 1:1. In some embodiments, the taconite material includes taconite powder and fine taconite aggregate having a ratio of 1:1. In some embodiments, the conductive material includes carbon-based nanoparticles in solution. In further embodiments, the EMI-resistant cementitious ink has a shielding effectiveness in accordance with ASTM D4935-18 of at least 4.0 dB.

The present invention provides a bidirectional energy-transfer system comprising: a thermally and/or electrically conductive concrete, disposed in a structural object; a location of energy supply or demand that is physically isolated from, but in thermodynamic and/or electromagnetic communication with, the thermally and/or electrically conductive concrete; and a means of transferring energy between the structural object and the location of energy supply or demand. The system can be a single node in a neural network. The thermally and/or electrically conductive concrete includes a conductive, shock-absorbing material, such as graphite. Preferred compositions are disclosed for the thermally and/or electrically conductive concrete. The bidirectional energy-transfer system may be present in a solar-energy collection system, a grade beam, an indoor radiant flooring system, a structural wall or ceiling, a bridge, a roadway, a driveway, a parking lot, a commercial aviation runway, a military runway, a grain silo, or pavers, for example.

In some implementations, a conductive concrete composition for providing improved shielding against electromagnetic radiation comprises cement, one or more supplementary materials, aggregates, one or more carbon products, and fibers. In some implementations, the composition comprises between about 5% and about 40% by weight of cement, between about 1% and about 20% by weight of one or more supplementary materials, between about 5% and about 80% by weight of aggregates, between about 1% and about 40% by weight of one or more carbon products, and between about 1% and about 10% by weight of fibers. In some embodiments, the one or more supplementary materials comprises ground granulated blast furnace slag (GGBS), the one or more carbon products comprises graphite, and the fibers comprise steel fibers. The aggregates can include normal weight, lightweight, and/or fine aggregates.

A multifunctional end cap catalyst is provided, comprising a multi-wall carbon nanotube with a multi-metal catalyst at the end cap. The catalyst contributes preferentially to growing a multi-wall carbon nanotube through a methane pyrolysis process at a lower temperature, and then infuses the nanotube into a host material, such as concrete, asphalt, polymer, or steel, improving functional parameters including thermal conductivity, electrical conductivity, wettability, flexural strength, tensile strength, or interfacial bonding strength. The catalyst can also increase the host material's decrease phonon scattering or interfacial resistance, and lower the final defect density of the multi-wall carbon nanotube. The multifunctional end cap catalyst can be composed of various metals, including copper, nickel, and manganese, and can achieve specific functional states, such as oxidized or functionalized metal states, without increasing the final defect density.

This synthetic stone can be used as electrical energy storage which acts like a supercapacitor and invention also discloses a preparation method thereof. According to this invention, geopolymer (11) and cement (12) are being taken as materials for an electrolyte. A supercapacitor of the present invention comprises a geopolymer (11) and cement matrix (1) and a positive and negative steel electrode (2, 3), whereby the steel electrodes (2, 3) are arranged in the matrix (1), and the matrix (1) is prepared from conductive mortar. The conductive mortar (1) comprises fly ash, cement (12), gravel and sand, alkali activator (KOH and SiO.sub.2) (13), and some additives (14) of synthetic stone compounds such as poly carboxylate ether, retarder, lignosulfonate, ethylene-vinyl acetate, hydroxypropyl methyl cellulose, pigment and carbon black. This supercapacitor synthetic stone is simple in structure and is based on a particular formulation.

A fresh concrete composition for producing a magnetizable concrete, including 250-450 kg/m.sup.3 of cement, 50-150 kg/m.sup.3 of a mineral addition, 2900-3500 kg/m.sup.3 of aggregates containing magnetizable particles, and 100-150 kg/m.sup.3 water, wherein the sand volume is 60 vol.-%.