Caterpillar Tractor Co.

Glenn H Lenzen, Jr

Michael L Earle

Preston Lee Gale

Simon L Engel

An apparatus for fusibly bonding a powder coating material to a metal article includes a holding device for releasably supporting the article, a depositing device for controllably placing the powder coating material in a band onto a surface of the article, and a laser beam for controllably liquifying a portion of the band of powder and juxtaposed surface while minimizing heat transmission into the article and allowing rapid hardening of the portion of the band after removal of the laser beam to provide a surface layer having properties based substantially solely on the coating material and a relatively thin, strong region of interstitial bond between the surface layer and the article having properties based upon both the coating material and the article. An exemplary engine valve with a relatively fine metallurgical surface structure for increased hardness is disclosed.

Apparatus for fusibly bonding a coating material to a metal article

An engine valve has a valve body, a valve head, an annular metallic valve seat layer fusibly bonded to the valve head that has a relatively fine crystalline structure, and a thinner region of interstitial bond between the valve head and the valve seat layer than heretofore known.

Engine valve

A method for fusibly bonding a coating material to a metal article includes depositing such coating material in solid form on a surface of the article, substantially simultaneously thermally liquifying the coating material and the surface of the article by focusing a relatively high power continuous wave laser beam thereon, and removing the laser beam therefrom to allow cooling and hardening thereof so as to provide a solidified surface layer with a strong and relatively thin interstitial bond between the layer and the article. An exemplary engine valve with a relatively fine structure of the coating material for increased hardness is disclosed.

Method for fusibly bonding a coating material to a metal article

A method of heat treating a bore in a workpiece to increase its surface hardness is disclosed, including shaping an annular laser beam emanating from a source into an elongated focal pattern to provide a more evenly distributed energy level in cross section, directing the elongated focal pattern generally axially inwardly toward the bore, reflecting the elongated focal pattern from a mirror arrangement substantially transversely upon a surface of the bore to provide an instantaneously more uniformly hot heating zone thereat, and effecting relative motion between the workpiece and the mirror arrangement so that the bore is progressively scannably heat treated to minimize heating of the entire workpiece.

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Peoria, IL, United States of America

Glenn H Lenzen, Jr