Ferrous metal article having oxide coating formed from the base metal suitable for brake apparatus et al
AssigneeThe BFGoodrich Company
InventorsRobert Bianco, Thomas D. Nixon, John P. Swank
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Abstract
Disclosed is a ferrous metal article having a protective, adherent, wear resistant coating of metallic oxides and a method of forming a protective, adherent, wear resistant coating of metallic oxides on an iron-chrome article. The coating desirably has a thickness of from about 12.7 to about 102 microns (½ mil to about 4 mils) and is formed by exposure of the article to an oxidizing atmosphere, preferably air, preferably during heat treatment of the article.
Claims20
An article of manufacture comprising:
- a substrate of ferrous alloy having a wear resistant surface having a coating of metallic oxides including an outer iron oxide rich region, an underlying chromium oxide rich region that is cohesively attached to an inner cohesive nickel rich region of the base metal, wherein the coating is formed by oxidation of the surface of the article at a temperature of at least 880° C.
An aircraft brake assembly having a brake stack comprising a plurality of interleaved stator and rotor friction disks wherein at least one of the disks in the brake stack includes a plurality of torque drive notches spaced around its circumferential direction that are provided with drive inserts including a substrate of ferrous alloy having a wear surface, and a coating of metallic oxides including an outer iron oxide rich region and an inner chromium oxide rich region and an underlying cohesive nickel rich layer covering at least a portion of said wear surface, the brake assembly having increased dynamic stability against vibration during a braking event compared to an otherwise identical brake having a brake stack in which all of the drive inserts are formed of AMS 538F cobalt-base alloy.
Dependencies are inferred from the claim text.