The effect of microstructural inhomogeneity on thermal diffusivity in a rheocast component
2016 (English)In: La Metallurgia Italiana, ISSN 0026-0843, no 6, 57-60 p.Article in journal (Refereed) In press
The relationship between microstructural characteristics and thermal diffusivity of a rheocast component was investigated for two Al-Si-Mg-Fe alloys with low Si contents. The microstructural investigation of the components clearly depicted the formation of coarse solute-lean globular α1-Al particles during the slurry fabrication process and fine solute-rich α2-Al and α3-Al particles during the secondary solidification in the die cavity. The microstructural characterization was quantified based on the amount of α1-Al particles in different locations of the component. The result clearly revealed a presence of both longitudinal and transverse macrosegregation of solute-lean α1-Al particles in the rheocast component. The study of thermal diffusivity and hardness revealed that the regions of the component with a high fraction of α1-Al particles had a higher thermal diffusivity but a lower hardness. Silicon in the solid solution was observed to be a critical factor in reducing the thermal diffusivity. The comparison between the effect of longitudinal and transverse segregation on thermal diffusivity showed that the transverse segregation had a stronger impact.
Place, publisher, year, edition, pages
Milano: Associazione Italiana di Metallurgia , 2016. no 6, 57-60 p.
SSM casting, Aluminium Alloys, Inhomogeneity, Microstructure, Hardness, Thermal Diffusivity
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:hj:diva-30581OAI: oai:DiVA.org:hj-30581DiVA: diva2:937884
High Tech Die Casting 2016, Venice, 22-23 June, 2016.
FunderKnowledge Foundation, 20100280