Evaluation of the influence of hot forming to the resulting mechanical properties of Ti-6242

Important results from the project

The project aims to evaluate the influence of temperature and process history of relevance for hot forming on the mechanical properties of Ti-6424. Furthermore, the obtained geometry from a unique forming process are studied for three different titanium alloys which include cold forming, AM and welding as well as hot forming. In the project, SMF LaserTool in Blekinge AB participated in the production of highly accuracy test specimens and 3D scanning for evaluation of shape deviations of AM-processed and hot-formed titanium details.

Expected long term effects

The project has successfully demonstrated some influence of temperature and process history on the mechanical properties of Ti-6242. The material was challenging to mechanically test as the material exhibits fluctuating strain behavior, so-called serrated yielding. Furthermore, the project has shown that the unique hot forming process of AM-reinforced titanium sheets can generate parts within shape tolerance. These double-curved parts were hot-formed within the LIGHTest project where on-line physical tests enabled GKN to participate despite the ongoing Corona pandemic.

Approach and implementation

The project has successfully been carried out in a different activities such as designing specimens at SMF LaserTool, heat treatment and etching processing at GKN, mechanical testing and hotforming at RISE and evaluation of shape deviations through 3D scanning at SME. The interaction between this project and ongoing LIGHTest project successfully provided the opportunity to evaluate shape deviations and process parameters for three different titanium alloys. A final result meeting is scheduled to be held in May to discuss conclusions and possible continuation project.