Development of a Thermomechanical Deep Drawing Tool for a Concerted Phase Transformation
|Autoren:||Voges-Schwieger, K.; Behrens, B.-A.|
|Veröffentlichung:||Special issue of NETSU SHORI - Journal of the Japan Society for Heat Treatment, pp. 725-728, ISSN 0288-0490|
The changing world is setting new requirements in CO2 reduction considering new proposals for lightweight constructions e.g. in the automotive industry. One approach is the application of metastable austenitic steels to exploit the TRIP-effect (Transformation Induced Plasticity) by realizing local high-strength and ductile areas in one and the same part. Due to the martensite evolution in deep drawing processes the material experiences an increase in strain-hardening. The nature of phase transformation is mainly influenced by true strain, temperature and forming velocity. The forming of material at lower temperatures enhances the martensite formation while temperatures from T=313.15 K avoid this phenomenon. This work is presenting the design and application of an actively coolable and heating forming tool for deep drawing. The realized process temperatures are in the range of T=253.15 K up to T=353.15 K. The thermomechanical concept will be presented regarding the special heat treatments in combination with a concerted stretch out of material to increase the true strain locally.