A brake drum for a vehicle includes a friction ring and a drum body. The friction ring has grooves arranged on a radial outer surface along a circumference, and a coating formed on the grooves. The drum body is cast onto the radial outer surface of the friction ring so that the grooves are filled with a material of the drum body. The grooves include first grooves and second grooves. A first axial segment is formed at the friction ring in which the first grooves are introduced so that the first grooves are inclined relative to a first axial end of the friction ring. A second axial segment is formed at the friction ring in which the second grooves are introduced so that the second grooves are inclined in a direction which is opposite to that of the first axial segment. Each of the grooves have undercuts.

Technologies are described for a durable low friction coating (DLFC), which may be manufactured by mixing a binder, a filler, and one or more additives in liquid form, rolling the liquid mixture onto a coil material and curing for subsequent cutting and stamping. The DLFC may be used to coat an abutment clip or a brake shim directly onto a metal substrate or over an elastomer layer. Water-based binders may be used for environmentally friendly brake systems. In some examples, the binder in the DLFC may be in a range from at least 70 weight % to less than 95 weight %, the filler in a range from at least 1 weight % to less than 15 weight %, and the additives in a range from at least 0.2 weight % to less than 5 weight %.

A method for densifying porous annular substrates by chemical vapor infiltration, includes providing a plurality of unit modules including a support tray on which substrates are stacked, the support tray including a gas intake opening extended by an injection tube disposed in an internal volume formed by the central passages of the stacked substrates, the injection tube including gas injection orifices opening into the internal volume, forming stacks of unit modules in the enclosure of a densification furnace and injecting, into the stacks of unit modules, a gas phase including a gas precursor of a matrix material to be deposited within the porosity of the substrates.

A method for producing a composition containing a latex of a nitrile rubber of α,β-ethylenically unsaturated nitrile monomer unit of 8 to 60 wt % content, and an iodine value of 120 or less, an isothiazoline-based compound represented by formula (1), and a benzisothiazoline-based compound represented by formula (2), both in a content of 26 ppm by weight or more to the rubber, wherein adding both compounds to the latex at 2,000 ppm by weight/min or less, at 50° C. or lower, and the compounds in an aqueous state having 0.1 to 40 wt % concentration. ##STR00001## formula (1), R.sup.1 and formula (2), R.sup.4 represents a hydrogen atom, or a substituted or unsubstituted organic group; wherein formula (1) R.sup.2 and R.sup.3 represent a hydrogen atom, a halogen atom, or an substituted organic group; and formula (2), R.sup.5 represent a hydrogen atom, or an substituted organic group, and an integer “n” of 0 to 4.

A method of manufacturing a camshaft for a drum brake includes designing a tubular camshaft and thereafter forming the camshaft as a unitary body through, for example, an additive manufacturing process. The camshaft is designed with a first end portion configured for coupling to a brake actuator, a second end portion defining a cam configured to engage cam followers coupled to first and second brake shoes, rotation of the cam causing the first and second brake shoes to move between positions of engagement and disengagement with an associated braking surface, and an intermediate portion disposed between the first and second end portions. A wall thickness of at least one of the end portions and the intermediate portion is configured to achieve at least one of a predetermined torsional stiffness in the camshaft and vibration damping in the camshaft at a selected frequency.

A latex of a carboxyl group-containing nitrile rubber contains an α,β-ethylenically unsaturated nitrile monomer unit in a content of 8 to 60 wt % and having an iodine value of 120 or less, wherein the total content of potassium and sodium contained in the latex is 2,300 to 10,000 ppm by weight with respect to the whole latex.

A method of manufacturing a carbon structure can comprise: infiltrating the carbon structure with a silicon oxycarbide (SiOC) precursor sol; and densifying the carbon structure by chemical vapor infiltration (CVI) to form a carbon and ceramic matrix composite material, the carbon and ceramic matrix composite material comprising between 0% and 15% by weight of a plurality of ceramic particles from the ceramic compound, densifying the carbon structure including adjusting a temperature gradient across the carbon structure.

A hybrid torque tube for a brake assembly may comprise a tube portion having a centerline axis, and a conical back-leg portion extending from the tube portion. A stator spline may be formed on a radially outward surface of the tube portion. A foot may be formed on a radially inward surface of the tube portion. The tube portion is formed using a first manufacturing process and at least one of the conical back-leg, stator spline, or foot is formed using additive manufacturing.

A method for producing a multi-layered wet friction material includes providing a bottom layer, providing a top layer produced independently of the bottom layer from different materials, and bonding the bottom layer to the top layer. The bottom layer and the top layer may be produced from different formulations and supplied as raw papers. A formulation of the top layer may include twenty to sixty percent (20%-60%) filler, ten to forty percent (10%-40%) wood pulp, five to ten percent (5%-10%) aramid, and twenty-five to thirty-five percent (25%-35%) phenolic resin. A formulation of the bottom layer may include ten to fifty percent (10%-50%) filler, ten to forty percent (10%-40%) wood pulp, five to ten percent (5%-10%) aramid, five to fifteen percent (5%-15%) carbon, and twenty-five to thirty-five percent (25%-35%) phenolic resin.

A brake disc used for brake systems of motor vehicles, rail vehicles and aircrafts and the brake disc includes a brake disc body, wherein the brake disc body is an aluminum alloy brake disc body, the two working surfaces of the aluminum alloy brake disc body are respectively attached with a wear-resistant layer, the wear-resistant layers are wear-resistant layers made of ceramic high-temperature resistant metal matrix composite (MMC) reinforced materials, and the wear-resistant layers made of ceramic high-temperature resistant MMC reinforced materials metallurgically bond with the aluminum alloy brake disc body through a squeeze casting technique.