Date of Award
Open Access Master's Thesis
Master of Science in Materials Science and Engineering (MS)
Administrative Home Department
Department of Materials Science and Engineering
Committee Member 1
Committee Member 2
Dissimilar castings are under investigation due to their light-weighting opportunities within the automotive industry. In this case, dissimilar castings consist of a solid steel core and a poured aluminum component. The strength and integrity of the casting relies on the coherency of the bond between the two components; by optimizing the metallurgical component of the bonding phenomena, the weight and complexity of the insert can be reduced, further increasing the light-weighting opportunities. An interface comprised of intermetallics, generally Fe4Al13 and Fe2Al5, forms between the two components with the latter forming nearest the steel. Cerium and magnesium additions to the aluminum component of the casting were investigated to increase the integrity of the metallurgical bond. Five alloys, 99.99wt%Al, Al-5Mg, Al-6Ce, Al-10Ce, and Al-10Ce-5Mg, were utilized to study the effect of cerium and magnesium on the intermetallic growth through an immersion experiment. Three alloys, Al-6Ce, Al-10Ce, and Al-10Ce-5Mg, were used to investigate the interfacial shear strength through a pin extraction experiment. The magnesium containing alloys showed a large decrease in total intermetallic compound layer thickness and an increase in the interfacial shear strength. A possible mechanism for the thickness reduction was magnesium reducing the lattice parameters of Fe4Al13 and Fe2Al5 reducing the diffusion of aluminum through the layer.
Thomas, Matt, "EFFECT OF CERIUM AND MAGNESIUM ADDITIONS ON THE STRENGTH AND MORPHOLOGY OF THE INTERMETALLIC COMPOUND LAYERS IN ALUMINUM-STEEL DISSIMILAR CASTINGS", Open Access Master's Thesis, Michigan Technological University, 2020.