Verfahren zum Oberflächenhärten von Nockenwellen und Vorrichtung zur Durchführung des Verfahrens

摘要

A cast iron article 11, such as a cam shaft or rocker arm, is provided with an abrasion resistant integral hardened surface layer containing at least one hardening element chosen from Cr, Mo, Ni, W, V and Nb, the concentration on a weight percentage basis of said hardening element(s) being higher in said hardened layer than beneath said layer by applying a plasma arc (12) to the article surface (11a) and introducing the hardening element(s), in the form of powders (14) of the element(s) or alloys or compounds thereof, into the arc and thus into the molten metal pool (13) formed by the arc on the article surface.