Authors:
Piotr Malczyk | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
Dr. Tilo Zienert | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
Florian Kerber | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
Dr. Jana Hubálková | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
Dr. Gert Schmidt | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
Dr. Nora Brachhold | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
Prof. Dr.-Ing. habil. Christos G. Aneziris | Institute of Ceramics, Refractories and Composite Materials, Technische Universität Bergakademie Freiberg | Germany
The development and evaluation of novel Steel-based Composites for direct contact with liquid aluminum alloys has been carried out. The Steel Ceramic Composite consisted of 60 vol% 316L stainless steel powder and 40 vol% of MgO or TiO2 ceramic powder. The sample were manufactured using uniaxial pressing and subsequent surface preoxidation at 850, 1000 °C for 24 h.
The corrosion resistance of composite was investigated against molten AlSi7Mg0.3 alloy using wettability test, finger immersion tests, crucible corrosion tests and high temperature electrochemical measurements at 850 °C. Wettability tests were performed on the Hot Stage Microscope using adapted capillary purification technique. Finger immersion tests were carried out at 850 °C for 24 h, whereas crucible corrosion tests were carried out at 850 °C for 24 h and 168 h. Specimens after the corrosion tests were investigated using SEM/EDS and XRD, focusing on the phase formation at the composite/aluminum alloy interface. The corrosion phases formed in the aluminum alloy were investigated with the aid of SEM/EDS/EBSD with ASPEX AFA. Mechanical properties of composites were investigated using the three-point bending procedure at both ambient and elevated (850 °C) temperature.
The results show excellent corrosion resistance of developed Steel-MgO composite against long-term contact with molten aluminum alloy even for 168 h. It was revealed that 1000 °C surface preoxidation causes the formation of new phases based on MgO-FeO solid solution, which are stable in contact with liquid AlSi7Mg0.3. Moreover, composites exhibited promising mechanical properties with enhanced ductility both at room and elevated temperature.