Twin-Roll Strip Casting Process for the Production of Clad Strip - Twin-Roll Clad Casting

• Applicant: Professor Dr.-Ing. Gerhard Hirt
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2014 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 258106764

Cladded strips and plates are already used in a wide spectrum of applications and are produced in relatively significant volumes. However, the available processes for the production of clad products (cold and hot rolling, explosion cladding, alloy welding) are limited in the material combinations and due to long process chain or reduced productivity, too expensive for the application in high production volumes. Without any doubt, an increase in the application of inexpensive clad products and different material combinations would lead to significant technical, ecological and economic advantages. Developments in this direction were made in the aluminum industry by casting different aluminum alloys in a single ingot. It is not currently possible to transfer these technologies in the steel production due to the higher temperature range and the actual steel production processes limitations. An interesting alternative could be the continuous production of clad strip by twin-roll strip casting. Apparently only few researches have been conducted so far to investigate systematically and reliably the potential of thin strip casting for the production of clad strip. This process, in which strips with a thickness ranging from 1 to 3 mm can be cast, offers the important opportunity to produce clad strips with reduced energy consumption and emissions. In simplified trials performed at the IBF using short strip segments it was possible to demonstrate that due to the fast solidification process it is possible to join also very different material classes. As an example, copper and titanium strips embedded in a larger steel strip. Consequently, the proposed project aims at the following main targets:1. Prove the basic feasibility of the continuous cladding of metallic strips with the twin-roll strip casting process.2. Investigate the process limits in relation to the possible thickness ratio between cladding and clad material and the selected material combination.3. Evaluate the resistance of the joint in correlation to the casting parameters.To reach these targets, the proper strip thicknesses and casting parameters will be initially roughly defined with the help of a numerical model. An insertion system for the cladding strip will be designed and constructed and preliminary tests performed. Subsequently, the numerical model will be improved and a systematic experimental campaign will be aimed at the investigation of the process limitations and application potentials. The obtained clad strips will be characterized in terms of properties and processing possibilities.

• DFG Programme: Research Grants