Microstructural and mechanical characterization of an ultra-high-strength [Fe.sub.86.7][Cr.sub.4.4][Mo.sub.0.6][V.sub.1.1][W.sub.2.5][C.sub.4.7] alloy

• Published in: Journal of materials science 2012-01, Vol.47 (1), p.267
• Main Authors: Hufenbach, J, Kohlar, S, Kuhn, U, Giebeler, L, Eckert, J
• Format: Article
• Language: English
• Subjects: Alloys; Chemical properties; Degassing of metals; Hardness; Metals; Specialty metals industry; Thermal properties
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-011-5794-z

This study describes the correlation between microstructure and mechanical properties of an ultra-highstrength [Fe.sub.86.7][Cr.sub.4.4][Mo.sub.0.6][V.sub.1.1][W.sub.2.5][C.sub.4.7] (at.%) alloy manufactured under high cooling rates and pure conditions. The applied preparation conditions promote the formation of non-equilibrium phases such as martensite, retained austenite and special carbides already in the as-cast state. The carbides form a 3-dimensional skeleton-like structure between the retained austenite and the martensite. This hard and finely ramified carbide network distributed throughout the entire ingot is a specific characteristic of this alloy and important for its excellent mechanical properties. The material exhibits extremely high engineering compression strength of almost 5500 MPa combined with a large compression strain of about 23% due to deformation-induced martensite formation. Furthermore, the alloy possesses a high hardness and tensile strength in the as-cast condition. This combination of mechanical properties leads to an outstanding engineering material for a variety of structural applications in the automotive and tool manufacturing industry.