Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/87936
Type: Artigo de periódico
Title: Interconnection Of Thermal Parameters, Microstructure, Macrosegregation And Microhardness Of Unidirectionally Solidified Zn-rich Zn-ag Peritectic Alloys
Author: Dias M.
Brito C.
Bertelli F.
Rocha O.L.
Garcia A.
Abstract: In this work, the microstructural evolution of Zn-3.2wt%Ag (hypoperitectic) and Zn-8wt%Ag (hyperperitectic) alloys during transient unidirectional solidification is investigated. The experimental results include solidification thermal parameters such as the growth rate (VL), thermal gradient (GL) and tip cooling rate (T˙), which are related to the microstructural interphase spacing (λ) by proposed experimental growth laws. It is shown that, the classical lamellar eutectic growth law λ2V=constant, applies to the growth of the peritectic Zn-Ag alloys examined, despite the different values of the constant associated with each alloy composition. In contrast, it is shown that identical functions of the form λ=constant (GL)-14 (VL)-1/8, and λ=constant (T˙-1/3) can be applied to both alloys examined. Positive solute macrosegregation was observed in regions close to the bottom of the castings. The dependence of microhardness (HV) on the length scale of the microstructures (including that of a single phase Zn 0.8wt%Ag alloy: λC- cellular spacing) is examined. An experimental Hall-Petch type power law is proposed relating the resulting microhardness to λC for the single phase alloy, and despite the segregation profiles and the alloying differences of the hypoperitectic and hyperperitectic alloys, the average microhardnesses of these alloys is shown to be essentially constant and similar along the castings lengths.
Editor: Elsevier Ltd
Rights: fechado
Identifier DOI: 10.1016/j.matdes.2014.07.002
Address: http://www.scopus.com/inward/record.url?eid=2-s2.0-84920069892&partnerID=40&md5=0a97f4e3c6a6ef493ffca66ac71227aa
Date Issue: 2014
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
2-s2.0-84920069892.pdf3.05 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.