An exemplary shock absorber includes a damper tube, a damper piston, a piston shaft, and at least two different surface treatments. The damper tube includes an interior surface. The damper piston includes a piston surface that engages the interior surface. The piston shaft couples with the damper piston and includes a shaft surface that engages a fourth surface. The at least two different surface treatments are disposed on at least one of the interior surface and the shaft surface and create a corresponding plurality of coefficients of friction with at least one of the piston surface and the fourth surface respectively.

An exemplary shock absorber includes a damper tube, a damper piston, a piston shaft, and at least two different surface treatments. The damper tube includes an interior surface. The damper piston includes a piston surface that engages the interior surface. The piston shaft couples with the damper piston and includes a shaft surface that engages a fourth surface. The at least two different surface treatments are disposed on at least one of the interior surface and the shaft surface and create a corresponding plurality of coefficients of friction with at least one of the piston surface and the fourth surface respectively.

Torsional vibration damper for a drivetrain of a motor vehicle, having a primary element rotatable around a rotational axis and a secondary element rotatable relative to the primary element against an energy storage. The energy storage includes a helical compression spring unit. The helical compression spring unit is provided in a spring channel, and the helical compression spring unit includes an outer spring. The outer spring is formed as an arc spring and an inner spring is provided inside of the outer spring and virtually coaxial to the outer spring. The inner spring when disassembled from the helical compression spring unit is formed as a straight helical compression spring. The inner spring has a winding direction that is opposed to a winding direction of the outer spring and the inner spring when installed in the torsional vibration damper, is shorter than the outer spring by a value of x.

Described herein is an axle assembly and method of fabrication thereof. The axle assembly includes an axle having a first geometric shape housed within an axle housing having a second geometric shape. A shock absorber is located between the axle and the axle housing. The shock absorber supports the axle within the axle housing and comprises a first material and comprises a multi-sided configuration. The first geometric shape and the second geometric shape comprising polygons.

A piston and a method for producing a piston which can be secured to a piston sliding unit is provided. The piston sliding unit can be moved along its longitudinal axis in a cylinder. The piston includes a disc-shaped base body, wherein the piston is suitable and intended to seal two regions of the cylinder filled with a medium against one another. The method includes the following steps: a) producing the piston by pressing a material into a piston mold; b) smoothing the surface of the piston and/or pressing at least one flow path into the piston, by an embossing tool, which has a raised and rotationally symmetrical structure.

A piston and a method for producing a piston which can be secured to a piston sliding unit is provided. The piston sliding unit can be moved along its longitudinal axis in a cylinder. The piston includes a disc-shaped base body, wherein the piston is suitable and intended to seal two regions of the cylinder filled with a medium against one another. The method includes the following steps: a) producing the piston by pressing a material into a piston mold; b) smoothing the surface of the piston and/or pressing at least one flow path into the piston, by an embossing tool, which has a raised and rotationally symmetrical structure.

Described herein is an axle assembly and method of fabrication thereof. The axle assembly includes an axle having a first geometric shape housed within an axle housing having a second geometric shape. A shock absorber is located between the axle and the axle housing. The shock absorber supports the axle within the axle housing and comprises a first material and comprises a multi-sided configuration. The first geometric shape and the second geometric shape comprising polygons.

An exemplary shock absorber includes a damper tube, a damper piston, a piston shaft, and at least two different surface treatments. The damper tube includes an interior surface. The damper piston includes a piston surface that engages the interior surface. The piston shaft couples with the damper piston and includes a shaft surface that engages a fourth surface. The at least two different surface treatments are disposed on at least one of the interior surface and the shaft surface and create a corresponding plurality of coefficients of friction with at least one of the piston surface and the fourth surface respectively.

An exemplary shock absorber includes a damper tube, a damper piston, a piston shaft, and at least two different surface treatments. The damper tube includes an interior surface. The damper piston includes a piston surface that engages the interior surface. The piston shaft couples with the damper piston and includes a shaft surface that engages a fourth surface. The at least two different surface treatments are disposed on at least one of the interior surface and the shaft surface and create a corresponding plurality of coefficients of friction with at least one of the piston surface and the fourth surface respectively.

A shock absorber of the present invention includes an aluminum alloy-made cylinder having a plasma electrolytic oxide film on an inner periphery, a piston slidably inserted in the cylinder, and a piston rod movably inserted in the cylinder and connected to the piston. Further, a method for manufacturing a sliding member includes a plasma electrolytic oxidation treatment step of forming a plasma electrolytic oxide film with a film thickness of 40 m or more on a sliding surface of an aluminum alloy-made sliding member, and a polishing treatment step of polishing a surface of the plasma electrolytic oxide film.