Helmholtz-Zentrum Geesthacht, Tuesday, 22-May-2012 22:52:08 CEST
http://www.hzg.de/program/materials_systems/core/lwsm/magnesium/index.html.en

Magnesium based Materials

For novel ultralight-weight magnesium alloys substantial basic and application-orientated research is required in order to utilise these advanced materials for broad applications. In this programme, development of light-weight metal alloys is focused on high-strength wrought magnesium alloys for sheets and extrusions for selected demanding applications. In addition, cast magnesium alloys for use at elevated temperature and corrosion protection coatings for Mg-alloys and their multi-material components are developed. In order to fulfil requirements from industry and legislature, economic recycling Mg-alloys will be developed.

The research work planned in the area of magnesium based materials is partitioned into three groups, i.e. cast materials, wrought materials and corrosion behaviour of magnesium alloys. The aims are as follows:
  • New wrought materials with improved strength, ductility and almost isotropic properties
  • New magnesium alloys for elevated temperatures
  • Grain refinement of magnesium melts
  • Development of a magnesium recycling alloy
  • Surface coatings of magnesium materials for improved corrosion behaviour
The alloy development is coupled with a special regard to the processing and is also accompanied by modelling and simulation activities to achieve a full property spectrum of the materials and the processing chain. For cast and wrought materials grain refinement is of high importance to improve mechanical properties of components and to achieve high feedstock quality for wrought processing. Therefore a grain refining agent that works in all magnesium alloys needs to be developed. Since corrosion and corrosion protection are key issues for many engineering applications of magnesium alloys, corrosion research is fully integrated into the process of developing new alloys. In addition to improving the general corrosion performance and the impurity tolerance by specific alloy design, coating systems are being developed, which will also help to reduce the problem of galvanic corrosion of magnesium alloys used in combination with other metals. Following the demands from industry and legislature the development of a magnesium recycling alloy is of high importance. This alloy should have an adequate property profile in terms of strength and ductility as well as satisfying corrosion properties. Therefore the proper alloy compositions as well as impurity limits have to be determined. In addition to the described work a new field of research has been opened in the area of magnesium alloys for medical uses.

The R&D work planned for magnesium alloys spans a larger time frame than the current programme period from 2005 - 2009. While reliable results can be expected for the development of high temperature stable cast alloys, new wrought alloys have to be developed completely from scratch. This includes the entire processing chain starting with alloy development, the production of feedstock material, the wrought processing itself, development of appropriate joining technologies under special regard of chosen applications (Topic Mechanics and Joining of Leight-Weight Materials) and ends in a complete lifetime assessment. For both wrought and cast materials a recycling cycle needs to be established. While the processing like melting, cleaning of melts etc is mainly a technical problem, the limits of impurities of a recycling alloy are not defined. Therefore a special effort has to be undertaken to define the composition range, impurity limits and the property profile of a recycling alloy. All work is connected with the investigation of the corrosion behaviour of all magnesium based materials and the development of new coatings which are able to extend the area of applications for magnesium based materials.

The use of magnesium for medical applications has opened a completely new area of research. Here, advantage is taken of the generally weak corrosion resistance of magnesium alloys in combination with their biodegradability when implanted into the human body. Suitable, i.e., bio-compatible and controlled dissolvable alloy compositions need to be developed together with adapted processing routes.

Contact

Prof. Dr. Ing. Karl Ulrich Kainer

Phone: +49 (0)4152 87-2542

Fax: +49 (0)4152 87-2636

e-mail contact