Conductive Cementitious Material
A conductive cementitious material is disclosed that may be applied by conventional techniques. The conductive cementitious material has a plurality of metal-coated fibers precision chopped to longer lengths and a cementitious material base. The metal-coated fibers are dispersed throughout the cementitious material base to create a complex electron transport system facilitating conductivity sufficient to meet or exceed desired thresholds of conductivity. The complex electron transport system created facilitates conductivity with lower loadings. The additional unloaded portion of cementitious material base may receive other multifunctional materials. Exemplary conductive cementitious materials provide controlled heating of the cementitious material by applying an electrical current.
1 . A conductive cementitious material comprising:
a plurality of metal-coated fibers, the metal-coated fibers comprise a fibrous substrate and a metal coating and the metal-coated fibers being chopped to lengths of 0.125 inches to 0.5 inches; and
a cementitious material base, the metal-coated fibers being dispersed throughout the cementitious material base to a load level of between 0.01% to 2% by weight such that the conductivity of the conductive cementitious material ranges from 10 8 to 10 −3 ohm-cm.
2 . The conductive cementitious material of claim 1 wherein the fibers of the metal-coated fibers are selected from the group of fibers consisting of carbon fiber, cellulose fiber, cotton fiber, natural fibers, Kevlar, rayon, synthetic fibers, and nanofibers.
3 . The conductive cementitious material of claim 1 wherein the metal coating comprises nickel.
4 . The conductive cementitious material of claim 3 wherein the nickel metal coating comprises 15% to 50% of the metal-coated fibers by weight.
5 . The conductive cementitious material of claim 3 wherein the nickel metal coating comprises 15% to 30% of the metal-coated fibers by weight.
6 . The conductive cementitious material of claim 3 further comprising a functional additive.
7 . The conductive cementitious material of claim 6 wherein the functional additive is selected from the group of functional additives consisting of coloring particles, hardening agents, lubricating agents, magnetic particles, and any combination of such additives.
8 . The conductive cementitious material of claim 1 wherein the metal-coated fibers are chopped to the length of 0.25 inches.
9 . The conductive cementitious material of claim 1 wherein the load level of the metal-coated fibers dispersed throughout the cementitious material base ranges between 0.125% and 0.5% by weight provides ESD.
10 . The conductive cementitious material of claim 1 wherein the load level of the metal-coated fibers dispersed throughout the cementitious material base ranges between 1% and 2% by weight provides shielding against EMI.
11 . The conductive cementitious material of claim 1 wherein the load level of the metal-coated fibers dispersed throughout the cementitious material base ranges between 1% and 2% by weight provides controlled heating of the conductive cementitious material with the application of an electrical current.
12 . A multifunctional, conductive cementitious material comprising:
a plurality of metal-coated fibers, the metal-coated fibers comprise a fibrous substrate and a metal coating and the metal-coated fibers being chopped to lengths of 0.125 inches to 0.5 inches;
a functional additive, and
a cementitious material base, the metal-coated fibers being dispersed throughout the cementitious material base to a load level of between 0.01% to 2% by weight such that the conductivity of the conductive cementitious material ranges from 10 8 to 10 −3 ohm-cm.
13 . The multifunctional, conductive cementitious material of claim 12 wherein the fibers of the metal-coated fibers are selected from the group of fibers consisting of carbon fiber, cellulose fiber, cotton fiber, natural fibers, Kevlar, rayon, synthetic fibers, and nanofibers.
14 . The multifunctional, conductive cementitious material of claim 12 wherein the metal coating comprises nickel, and the nickel metal coating comprises 15% to 50% of the metal-coated fibers by weight.
15 . The multifunctional, conductive cementitious material of claim 14 wherein the nickel metal coating comprises 15% to 30% of the metal-coated fibers by weight.
16 . The multifunctional, conductive cementitious material of claim 12 wherein the metal-coated fibers are chopped to the length of 0.25 inches.
17 . The multifunctional, conductive cementitious material of claim 12 wherein the load level of the metal-coated fibers dispersed throughout the cementitious material base ranges between 0.125% and 0.5% by weight provides ESD.
18 . The multifunctional, conductive cementitious material of claim 12 wherein the load level of the metal-coated fibers dispersed throughout the cementitious material base ranges between 1% and 2% by weight provides shielding against EMI.
19 . The multifunctional, conductive cementitious material of claim 12 wherein the load level of the metal-coated fibers dispersed throughout the cementitious material base ranges between 1% and 2% by weight provides controlled heating of the conductive cementitious material with the application of an electrical current.
20 . The multifunctional, conductive cementitious material of claim 12 wherein the functional additive comprises one or more functional additives selected from a group of functional additives consisting of coloring particles, hardening agents, lubricating agents, magnetic particles, and conductive filamentary structures.