Researchers develop better protection technique for forging dies
22 Nov 2012
Hard or tough – very often, the manufacturers of forging dies must make a compromise here. A new technology now makes it possible to combine both characteristics and clearly expand the useful life of forging dies. The scientists will introduce the process at the Euromold trade fair, from 27 - 30 November in Frankfurt, Germany.
Forging dies must withstand a lot. They must be hard so that their surface does not get too worn out and is able to withstand massive changes in temperature and handle the impact of blows of the forge. However, the harder a material is, the more brittle it becomes - and forging dies are able to handle the stress from the impact less efficiently.
Therefore, the manufacturers have had to find a compromise between hardness and strength. One of the possibilities is to surround a semi-hard, strong material with a hard layer. The problem is that the layer rests on the softer material and can be indented by blows, like the shell of an egg.
Researchers from the Fraunhofer Institute for Production Technology IPT in Aachen, Germany, have now developed an alternative.
''The forging dies we have been working on have a useful life that is up to twice as long,'' explains Kristian Arntz, head of department at the IPT.
Arntz explains, ''We are using a working material that is less hard and able to handle the impact stress well. We melt the uppermost layer of the material with a laser and introduce a powder into the melt material that is used to chemically alter the characteristics of the material. We have therefore achieved a large degree of hardness in the upper millimeter.''