Manufacture of forge dies and recovery thereof

This sector has traditionally used shinking electrodischarge (SEDM) for the manufacture of forging dies in treated steels of approximately 40 HRC of hardness. Nevertheless, the simplicity of the cavities, wide tolerances and roughness requirements to be reached have made this one of the high speed milling star applications.

In the last eight years there has been a real migration from (SEDM) to HSM. In this sector, development times of new series are critical given the high competition between forgings, thus the reduced HSM process times is a highly important factor. In Fig. we can see two die cases, one medium-sized and the other small. Both are high speed machined in under 2 hours from treated steel (already hardened) to over 40 HRC. High speed milling also allows dies to be remachined for their recovery. Once used in the forging process some parts of the die are worn out, so welded material is added. After this process it is remilled at high speed, in this case a somewhat uneven material which co-exists with the original, i.e. additions and even over-tempered areas. The final result is a die ready for forging again.

Fig.9 Forging die of securing element and a suspension bearing.