Abstract: An improved friction-welding process for effecting a joint between steel and nodular graphite-containing cast iron by using (i) a short friction-generating time so as to minimize diffusion of carbon into steel and (ii) an elevated forging pressure so as to effect a quantitative ejection of carburized melt but avoid formation of a weld laminate, is provided, as well as a nodular graphite-containing cast iron of grade 40.3 S, suitable for use in friction-welding and comprising about 280-320 graphite nodules per mm.sup.2, 280-300 ferrite grains per mm.sup.2 and a spherulite proportion of about at least 95% by weight of the graphite precipitations.
Type:
Grant
Filed:
December 28, 1987
Date of Patent:
December 27, 1988
Assignees:
Walter Hundhausen GmbH & Co. KG, KUKA Schweissanlangen+Roboter GmbH
Inventors:
Wolfgang Farrenkopf, Heinrich Gruenauer, Manfred Menzinger, Joachim von Hirsch, Reinhard Opitz