Wear characteristics of STD61 tool steel according to repairing methods for Al porthole extrusion die: Direct metal deposition, welding, parent material

Abstract

In the aluminum porthole extrusion process, excessive wear occurs on the surface of mandrel. This study evaluates the applicability of direct metal deposition (DMD), a 3D printing process, for repairing the hot aluminum extrusion die. The wear characteristics of three die repairing methods (parent-STD61, DMD-STD61, and welded-STD61) were compared through a high-temperature pin-on-disk wear test that considers the aluminum extrusion temperature. The results confirm that DMD results in superior wear characteristics when compared to overlay welding repair method. Further, the wear resistance of DMD-STD61 is similar to that of parent-STD61. The application of the DMD process is expected to yield a wear life similar to that of the parent STD61.