An example method includes forming an interlayer on a carbon fiber fabric to form a composite fiber fabric. The interlayer comprises a binder. The method further includes winding the composite fiber fabric around a core to form a composite fiber preform comprising a plurality of layers defining an annulus extending along a central axis. The method further includes densifying the composite fiber preform.

Brake pads are prepared using a LS (Low Steel) or NAO (Non-Asbestos Organics) type friction material formulation and at least one friction surface of a brake disc intended to cooperate in use with a brake pad that is coated with an anti-wear and anti-corrosion coating with adequate plasticity in order to have a reduced propensity to form micro-cracks under conditions of tribo-mechanical stress, chosen from the amongst the group consisting in: particles of chromium carbide (Cr.sub.3C.sub.2) dispersed within a metallic matrix consisting of an alloy of NiCr; particles of a combination of several metallic materials in order to create a metallic compound consisting of an alloy of FeNiCrMoSiC (iron-nickel-chromium-molybdenum-silicon-carbon).

Brake pads are prepared using a formulation of friction material of the copper-free type (Low-Steel or Organic Non-Asbestos) and at least one friction surface of a brake disc, which is intended to cooperate with the brake pad, is covered with an anti-wear and anti-corrosion coating consisting of a surface layer of chromium carbide particles (Cr3C2) dispersed in a metallic matrix consisting of a NiCr alloy, and coupled to a second layer consisting of selected combinations of metallic materials, chosen from the group consisting of: Cr3C2-high density NiCr, NiAl alloys, FeNiCrMoSiC alloys, metallic nickel, NiCr alloys, and/or any combination of the above.

Method for producing a friction material, including the following steps in sequence: mixing an aluminosilicate source with an alkaline silicate solution to form a geopolymer, adding a friction mix to the geopolymer solution of the previous step to obtain a slurry, casting the slurry in a mold at temperature between room temperature and 120° C. and for between 5 min and 2 h and demolding to obtain a pad, attaching a backplate to the pad, curing for a time between X and Y hours at a temperature of between X and Y. The friction material obtained with the method is for the manufacture of friction layers/blocks for friction elements such as braking elements, including vehicle brake pads or blocks, and/or friction discs.

A friction material presents a friction-generating surface and a bonding surface opposite the friction-generating surface. The friction material includes unbranched fiber having a diameter of from 0.5 to 50 μm and a length of from 0.2 to 15 mm, branched fiber having a diameter of from 1 to 50 μm, and a resin disposed throughout the friction material. The friction material is substantially free of particles and defines a plurality of pores having a pore size distribution with a D10 value of from 5 to 15 μm, a D50 value of from 15 to 30 μm, and a D90 value of from 30 to 60 μm.

A method for densifying one or more porous substrates with pyrolytic carbon by chemical vapour infiltration, includes admitting, at the inlet of the densification furnace, a reactive gaseous phase including at least one pyrolytic carbon precursor; reacting at least a fraction of the reactive gaseous phase with the porous substrate or substrates; extracting, at the outlet of the densification furnace, gaseous effluents originating from the reactive gaseous phase; reintroducing, with the reactive gaseous phase admitted at the inlet of the densification furnace, at least a fraction of the gaseous effluents extracted at the outlet of the furnace, wherein the fraction of the gaseous effluents introduced with the reactive gaseous phase includes at least one polyaromatic hydrocarbon compound.

A friction member according to an embodiment is a friction material having a copper content of less than 5 wt %, the friction material including a titanic acid salt having a content of 1 wt % or more and 8 wt % or less, a cryolite powder having a content of 0.5 wt % or more and 5 wt % or less, and an iron oxide powder having a median diameter of 15 to 30 μm (D50) and a content of 1 wt % or more and 10 wt % or less.

Provided is a friction material that includes a boron-containing solid lubricant. The friction material may be used to form a brake pad for automotive vehicles. The friction material may include, by weight, about 1.0% to about 6.0% of the boron-containing solid lubricant, about 5.0% to about 15.0% of a fibrous or powdered metal material, an abrasive, an organic filler, an inorganic filler, and a binder. Advantageously, an antimony free and copper free friction material of the present disclosure may still achieve high fiction performance and long pad life, providing a more environment friendly solution to brake systems.

There are provided a friction material composition containing no copper or having a reduced content of copper that can provide a friction material in which the stability of the friction coefficient after standing in a cold environment, the abrasion resistance, and the low rust fixation properties are excellent, and squeal (particularly low temperature squeal) is suppressed, and a friction material obtained by molding the friction material composition, and a friction member using the friction material. The friction material composition is specifically a friction material composition comprising a bonding material, an organic filler, an inorganic filler, and a fiber substrate, in which the friction material composition comprises no copper, or has a content of copper of less than 0.5% by mass in terms of a copper element even if comprising the copper, and comprises, as the organic filler, cashew particles to which a silicone resin adheres.

The present disclosure provides systems and methods for forming a composite structure comprising rotating a base layer of an apparatus for forming the composite structure about an axis of rotation, transferring carbon short fibers from a first vibratory feed ramp onto the base layer in order to form a plurality of fibrous layers in the composite structure, and vibrating the first vibratory feed ramp during the transferring the carbon short fibers. The base layer may comprise an annular shape.