Making amorphous steel in air by rare earth microalloying

Recently great advancement in the fabrication of structural amorphous steels (SASs) with large cross-section sizes has been obtained. One of the remained key problems for the manufacturability and the application of SASs is that their glass-forming ability is very sensitive to the processing environments. Here we present the discovery that the bulk amorphous alloy Fe44Mn11Cr10Mo12C15B6Ho2 has high oxygen resistance and can be prepared by conventional copper-mold casting method in air atmosphere. Rod-shaped amorphous samples of diameter up to 6 mm at least have been fabricated successfully. This amorphous steel alloy showed high glass-forming ability and good manufacturability. The beneficial effects of the addition of holmium on the glass-forming ability and oxygen resistance during the SAS formation are explored.