A bicycle disc brake rotor, having a rotational center axis, comprises a base portion including iron and a surface portion including iron, aluminum, and chrome. The surface portion is formed on an external surface of the base portion. A concentration gradient of chrome of the surface portion is formed in an axial direction parallel to the rotational center axis.

A wear-resistant coating made from an iron alloy composition on brake disc brake surfaces is disclosed. The wear-resistant coating has 0.5 to 2% by weight C, 3 to 13% by weight Al and a residual portion of Fe supplementing the 100% by weight. A method for coating the brake disc is also disclosed.

A brake body according to the present disclosure has a coating layer which contains an iron-based amorphous alloy and is formed on a contact surface at which a friction means rubs against the brake body to generate braking force which the brake body is rotated. The coating layer has a low friction coefficient and thus generates less dust during braking. The coating layer also has high corrosion resistance and wear resistance and may thus guarantee high performance and good price competitiveness when applied to a brake base material produced at low cost.

A brake rotor assembly can include a structural part having a receiving surface and at least one friction surface parts having a contact surface. The friction surface part can be fixably attached to the receiving surface of the structural part such that the contact surface faces away from the receiving surface of the structural surface to form at least part of an annular braking surface arranged concentrically around an axis of rotation of the structural part.

A brake rotor for a motor vehicle having a composite structure may include an annular body defining opposite friction surfaces of the brake rotor. The annular body may include a core made of a lightweight, magnesium-based alloy; a thermal barrier layer made of a thermally insulating material disposed on the core; and a wear-resistant layer made of an AlFeSiZr alloy of aluminum (Al)+iron (Fe)+silicon (Si)+zirconium (Zr) that is disposed on the core over the thermal barrier layer. The wear-resistant layer may define a first one of the opposite friction surfaces of the annular body.

A braking band having an annular band body arranged around a rotation axis and made of one of gray cast iron, steel, aluminum or alloys thereof, has at least one braking surface having an activated band body portion for increasing adhesive capacity of at least one protective surface coating placed on the surface of the activated band body portion and having at least one material with elevated resistance to abrasion. The activated band body portion is arranged on the surface of the annular band body to form an outermost layer of the braking band with the at least one protective surface coating and has a rough profile having at least one channel delimited by at least one pair of projections, extending along a path at least partially surrounding the rotation axis and having a channel bottom and a first channel side forming an acute angle with the channel bottom and an opposite second channel side forming an obtuse angle with the channel bottom.

The invention relates to a brake drum assembly for braking at least one vehicle wheel that rotates about a rotation axis, the brake drum assembly comprising: a brake drum configured to rotate about the rotation axis and having a ring section extending circumferentially about the rotation axis and an end wall section extending at an angle to the rotation axis, the brake drum having an inner surface bounding at least part of a receiving space of the brake drum; at least one brake dust collector that faces an outer surface of the brake drum, wherein the brake drum comprises at least one through-hole providing a path through which brake dust can move from the receiving space to the dust collector.

A rotation braking device includes a cage disposed so as to be movable between an engagement position at which engagement elements are engaged with an inner member and an outer member, and a disengagement position at which the engagement elements are disengaged from the inner member and the outer member; a centering spring rotationally fixed to the cage; an axially movable friction member rotationally fixed to the cage; a separation spring for biasing the friction member in the direction away from an electromagnet via an armature; and a friction surface portion configured to axially receive the biased friction member and to apply a circumferential force to the friction member. The friction member is attracted to the armature when the electromagnet is energized. A surface treatment for reducing friction resistance is applied to at least one of opposed contact surfaces of the friction member and the armature.

A method of refurbishing a steel-shell brake drum that includes superheating a worn-out brake drum until the worn-out brake drum is glowing hot. The worn-out brake drum includes a steel shell and a worn-out, gray-iron layer bonded to an inside surface of the steel shell. The method further includes centrifugal casting additional molten iron to the gray-iron layer to increase the radial thickness of the gray-iron layer.

A vehicle braking component having a composite structure includes a brake core comprising an aluminum alloy, the brake core defining a core surface, a thermal barrier layer comprising a thermally insulating material, and an adhesion layer between the core surface and the thermal barrier layer to facilitate adhesion between the thermal barrier layer and the brake core. The adhesion layer includes a metal. The vehicle braking component includes a wear-resistant layer on the thermal barrier layer. The wear-resistance layer includes an iron-aluminum-silicon-zirconium alloy and defines a friction surface of the vehicle braking component.