Influence of microstructure and heat treatment on thermal conductivity of rheocast and liquid die cast Al-6Si-2Cu-Zn alloy
2016 (English)In: International Journal of Cast Metals Research, ISSN 1364-0461, E-ISSN 1743-1336, Vol. 29, no 4, 202-213 p.Article in journal (Refereed) PublishedText
Thermal conductivity of a rheocast component made from Stenal Rheo1 (Al-6Si-2Cu-Zn) alloy was investigated in as-cast, T5 and T6 conditions. The thermal conductivity measurement in different locations showed variation of this property throughout the rheocast component. The results of microstructural investigation revealed that the ratio of solute-lean α1-Al particles formed during slurry preparation to fine solute-rich α2-Al particles formed during secondary solidification had significant influence on thermal conductivity. The reduced amount of solutes in the α1-Al particles was determined as the root cause of higher thermal conductivity. A linear relation between the fraction of precipitates and the increase in thermal conductivity was obtained and silicon in solid solution is shown to have a dominant influence. As silicon was precipitated during the heat treatment, thermal conductivity increased. For an optimal combination of thermal and mechanical properties, it is therefore important to use an ageing temperature above the temperature of Si precipitation.
Place, publisher, year, edition, pages
2016. Vol. 29, no 4, 202-213 p.
Aluminium alloy, High-pressure die casting, Microstructure characteristics, Rheocasting, Thermal conductivity, Aluminum, Aluminum alloys, Copper alloys, Die casting, Heat treatment, Microstructure, Silicon, Thermal conductivity of solids, Zinc, Ageing temperature, High pressure die casting, Microstructural investigation, Optimal combination, Si precipitations, Thermal and mechanical properties, Thermal conductivity measurements
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:hj:diva-31227DOI: 10.1080/13640461.2015.1125990ISI: 000378146800003ScopusID: 2-s2.0-84978732257OAI: oai:DiVA.org:hj-31227DiVA: diva2:952018