Laser hardening low-carbon steel damper tubes

Abstract

A damper assembly includes a damper tube having a tubular shape defining an inner surface and extending for an axial length. The damper assembly also includes a rod disposed at least partially within the damper tube, and a piston connected to the rod and slidably disposed within the damper tube and configured to contact the inner surface of the damper tube along a stroke region less than the axial length. The inner surface of the damper tube includes a hardened surface including martensite and extending along the stroke region and less than the axial length of the damper tube. A method of treating a damper tube includes directing a laser beam onto an inner surface of the damper tube along a stroke region and less than an axial length of the damper tube and to cause steel of the inner surface of the damper tube to form a hardened surface.

Dependencies are inferred from the claim text.