Thixocasting of an A356 alloy: Fluidity, porosity distribution and thermomechanical fatigue behavior


Autoria(s): FREITAS, E. de; FERRANTE, M.; Ruchert, C. T.; BOSE FILHO, W. W.
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

18/10/2012

18/10/2012

2008

Resumo

An extensive set of experiments was performed on a semi-solid A356 alloy in order to assess its flow behavior, mechanical properties, microstructural evolution and porosity level. Three different microstructural conditioning techniques (raw material preparation) were employed: deformation recrystallization, magnetohydrodynamic stirring and low temperature pouring. Measurement of microstructural parameters such as Al-alpha particle size, shape factor, contiguity and entrapped liquid showed a relative equivalency among the various conditioning techniques. It was found that the strongest influence on semi-solid slurry fluidity is exerted by the mould temperature. Tensile properties and porosity levels were measured on a demonstration part produced with different slurry ingate velocities. Results showed similar strength levels among all thixocast samples, a strong correlation between elongation and pore volume fraction and porosity levels much lower than the typical figure for permanent mould or die cast Al-Si alloys. Finally, thermomechanical fatigue tests results were much more favorable to the semi-solid material when compared with the conventionally cast alloy, a result attributed to lower porosity, spheroidal shape of the Al-alpha phase, and refined Si eutectic particles. alpha 2007 Elsevier B.V. All rights reserved.

Identificador

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, v.479, n.1/Fev, p.171-180, 2008

0921-5093

http://producao.usp.br/handle/BDPI/18033

10.1016/j.msea.2007.06.037

http://dx.doi.org/10.1016/j.msea.2007.06.037

Idioma(s)

eng

Publicador

ELSEVIER SCIENCE SA

Relação

Materials Science and Engineering A-structural Materials Properties Microstructure and Processing

Direitos

restrictedAccess

Copyright ELSEVIER SCIENCE SA

Palavras-Chave #A356 #semi-solid #microstructure #mechanical properties #CAST #MICROSTRUCTURE #ALUMINUM #MODEL #Nanoscience & Nanotechnology #Materials Science, Multidisciplinary
Tipo

article

original article

publishedVersion