Microstructural Evaluation Of Rapidly Solidified Al-7Cr Melt Spun Ribbons

• Published in: Materiali in tehnologije Vol. 41; no. 6; pp. 283 - 287
• Main Authors: Jurci, Peter, Domankova, Maria, Hudakova, Maria, Sustarsic, Borivoj
• Format: Journal Article
• Language: Slovenian
• Published: 01.11.2007
• ISSN: 1580-2949; 1580-3414

The use of conventional bulk materials is limited by segregation phenomena, which are generated during the solidification and cannot be eliminated in the solid state. The introduction of rapid-solidification technology (RST) into material processing overcame some of the problems of unacceptable material quality and broadened the range of materials that it is possible to fabricate. The use of conventional ingot metallurgy for the fabrication of aluminium alloys containing a large amount of elements with a low diffusion coefficient is impossible because coarse, hard and brittle intermetallics are formed and the alloys have poor mechanical properties. The use of RST makes it possible to produce these alloys with an improved microstructure; however, before industrial production the structure and properties of the rapidly solidified semi-products as well as the consolidated bulk product must be evaluated systematically. In this paper, melt-spun ribbons, made under various conditions from a binary Al-7%Cr, alloy are investigated. The structure consisted of a supersaturated Al solid solution with a high dislocation density, precipitates of chromium-rich phases and rosette-like spherolites formed from the Al solid solution and the Al7Cr intermetallic phase. The type of phases is related to the processing conditions in only a very limited way.