REIBUNGSGESCHWEISSTES GESTEINBOHRWERKZEUG UND VERFAHREN ZU SEINER HERSTELLUNG

摘要

A friction welded product for rock drilling and method for manufacturing thereof, the product including a first component (25) and a second component (22) of parent material joined by a friction weld (27). The components have a central inner passage (26) and both components are made from a steel having a chemical composition such that the hardness in the most tempered part of the heat affected zone close to the weld is at least the same as that of the core hardness of the rod. Further, the product exhibits normal hardness when cooled to room temperature subsequent to the friction welding thereby having a minimum core hardness at the heat affected zone above 390 HV1.