A steel cord for reinforcing a breaker or belt ply in a rubber tire having a core group and a sheath group. The core group consists of two to four core steel filaments with a first diameter dc and the sheath group consists of one to six sheath steel filaments with a second diameter ds. The ratio dc/ds of the first diameter dc to the second diameter ds ranges from 1.10 to 1.70. The two core steel filaments are untwisted or have a twisting step greater than 300 mm. The sheath group is twisted around the core group with a cord twisting step in a cord twisting direction. The ratio of the difference in residual torsions of the core group and the sheath group to the difference in saturation level between the core group and the sheath group ranges from 0.10 to 0.65, preferably from 0.10 to 0.60.

A steel cord for reinforcing a breaker or belt ply in a rubber tire having a core group and a sheath group. The core group consists of two to four core steel filaments with a first diameter dc and the sheath group consists of one to six sheath steel filaments with a second diameter ds. The ratio dc/ds of the first diameter dc to the second diameter ds ranges from 1.10 to 1.70. The two core steel filaments are untwisted or have a twisting step greater than 300 mm. The sheath group is twisted around the core group with a cord twisting step in a cord twisting direction. The ratio of the difference in residual torsions of the core group and the sheath group to the difference in saturation level between the core group and the sheath group ranges from 0.10 to 0.65, preferably from 0.10 to 0.60.

Disclosed are a metal wire, a manufacturing method therefor, and a tire. The metal wire is made by twisting a filament; an outer peripheral surface of the filament is covered with a CuMZn alloy coating; the outer peripheral surface of the filament is also covered with a CuZn alloy coating; the metal wire is made of at least one filament; an area covered by the CuMZn alloy coating is 10%-90% of an area of the outer peripheral surface of the filament, and the rest is the CuZn alloy coating; M in the CuMZn alloy coating is selected from one or two of Co, Ni, Mn, or Mo; the mass fraction of Cu in the CuMZn alloy coating is 58%-72%, the mass fraction of M in the CuMZn alloy coating is 0.5%-5%, and the balance in the CuMZn alloy coating is Zn and inevitable impurities.

Disclosed are a metal wire, a manufacturing method therefor, and a tire. The metal wire is made by twisting a filament; an outer peripheral surface of the filament is covered with a CuMZn alloy coating; the outer peripheral surface of the filament is also covered with a CuZn alloy coating; the metal wire is made of at least one filament; an area covered by the CuMZn alloy coating is 10%-90% of an area of the outer peripheral surface of the filament, and the rest is the CuZn alloy coating; M in the CuMZn alloy coating is selected from one or two of Co, Ni, Mn, or Mo; the mass fraction of Cu in the CuMZn alloy coating is 58%-72%, the mass fraction of M in the CuMZn alloy coating is 0.5%-5%, and the balance in the CuMZn alloy coating is Zn and inevitable impurities.

A process for depositing, with forward progression, graphene on the surface of a metallic or metallized continuous reinforcer, at the periphery of which is positioned a layer of surface metal chosen from copper, nickel and copper/nickel alloys, comprises at least one stage of flame spray pyrolysis (FSP), under a reducing atmosphere, of a carbon precursor which generates, in the flame, at least one carbon-based gas such as carbon monoxide which is sprayed onto the surface of the reinforcer in forward progression, and is decomposed thereon to form one or more graphene layers at the surface of the surface metal; an additional stage of graphene functionalization makes it possible to adhere the reinforcer to a polymer matrix such as rubber.

A process for depositing, with forward progression, graphene on the surface of a metallic or metallized continuous reinforcer, at the periphery of which is positioned a layer of surface metal chosen from copper, nickel and copper/nickel alloys, comprises at least one stage of flame spray pyrolysis (FSP), under a reducing atmosphere, of a carbon precursor which generates, in the flame, at least one carbon-based gas such as carbon monoxide which is sprayed onto the surface of the reinforcer in forward progression, and is decomposed thereon to form one or more graphene layers at the surface of the surface metal; an additional stage of graphene functionalization makes it possible to adhere the reinforcer to a polymer matrix such as rubber.

A reinforcement means for molded and extruded articles such as tires has a metal structure with a layer of silica gel bonded thereto. The silica gel bonds the reinforcement means to the rubber compound during the molding/vulcanization of the rubber compound without the need for a slow curing stage. The silica gel may be applied to the metal structure by a sol-gel process with the gel formed by drying the sol at a temperature up to 150 C. The reinforcement means is preferably a cable formed from steel wires coated with the silica gel. To further improve bonding of the silica gel to the rubber compound, an organosilane bonding agent may be included in the rubber compound or the reinforcing means provided with a second layer comprising an organosilane as a bonding agent. The reinforcement means are particularly useful for strengthening and providing geometric stability to tires.

A reinforcement means for molded and extruded articles such as tires has a metal structure with a layer of silica gel bonded thereto. The silica gel bonds the reinforcement means to the rubber compound during the molding/vulcanization of the rubber compound without the need for a slow curing stage. The silica gel may be applied to the metal structure by a sol-gel process with the gel formed by drying the sol at a temperature up to 150 C. The reinforcement means is preferably a cable formed from steel wires coated with the silica gel. To further improve bonding of the silica gel to the rubber compound, an organosilane bonding agent may be included in the rubber compound or the reinforcing means provided with a second layer comprising an organosilane as a bonding agent. The reinforcement means are particularly useful for strengthening and providing geometric stability to tires.

A steel cord that is suitable for reinforcing rubber articles such as tires. The inventive steel cord enables to completely eliminate the presence of cobalt in a tire when combined with the proper cobalt free compound. Advantageously the steel cord adheres equally well to rubbers containing organic cobalt salts. The inventive wire is different from prior art steel cords in that the brass coating now comprises iron particles. The iron particles have a size between 10 nm and 10 000 nm. The presence of iron mitigates the adhesion retention loss of the rubber to steel cord bond in a hot and humid environment. It is a further advantage that the inventive steel cord does not contain any intentionally added cobalt thereby contributing to the elimination of harmful substances in the production area as well as the environment.

A steel cord that is suitable for reinforcing rubber articles such as tires. The inventive steel cord enables to completely eliminate the presence of cobalt in a tire when combined with the proper cobalt free compound. Advantageously the steel cord adheres equally well to rubbers containing organic cobalt salts. The inventive wire is different from prior art steel cords in that the brass coating now comprises iron particles. The iron particles have a size between 10 nm and 10 000 nm. The presence of iron mitigates the adhesion retention loss of the rubber to steel cord bond in a hot and humid environment. It is a further advantage that the inventive steel cord does not contain any intentionally added cobalt thereby contributing to the elimination of harmful substances in the production area as well as the environment.