Fracture toughness and corrosion resistance of semisolid AlSi5 alloy

Journal Article · Wed May 04 04:00:00 EDT 2011 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3589655· OSTI ID:21516698

Pola, A; Montesano, L; Gelfi, M; Roberti, R ^[1]

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1. University of Brescia-Dept. of Mechanical and Industrial Engineering (Italy)

The aim of this work was to investigate fracture toughness and corrosion resistance of semisolid AlSi5 castings, compared to samples obtained from conventional casting operations. In order to have a semisolid microstructure, the melt alloy was treated by means of ultrasound during solidification and then poured into permanent moulds. Mechanical properties of semisolid and conventional castings were compared by means of ultimate tensile strength (R{sub m}), yield stress (Rp{sub 02}) and hardness (HV) measurements. Fracture mechanics tests were carried out on Single Edge Notched Bend (SENB) specimens, machined from castings, and pre-cracked by fatigue. These tests were performed to determine the effect of the microstructure on the J-Integral resistance (J-R) behavior and to deeply understand the ductile fracture behaviour of semisolid parts. The J-Integral versus spaced crack extension (J-{Delta}a) curves showed an improved resistance of the semisolid microstructure, due to the higher ductility. Finally, the corrosion behaviour of semisolid samples was compared to that of castings coming from solidification of fully liquid alloy by means of electrochemical potentiodynamic polarization tests. It was observed that the globular microstructure offers better quality, in terms of higher mechanical properties, as a consequence of a more uniform distribution of the solute.

• OSTI ID: 21516698
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1353; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALLOY SYSTEMS
ALLOYS
ALUMINIUM ALLOYS
BINARY ALLOY SYSTEMS
CHEMICAL REACTIONS
CHEMISTRY
CORROSION
CORROSION RESISTANCE
CRACKS
DISTRIBUTION
DUCTILITY
ELECTROCHEMISTRY
FAILURES
FATIGUE
FRACTURE MECHANICS
FRACTURE PROPERTIES
FRACTURES
HARDNESS
MECHANICAL PROPERTIES
MECHANICS
MICROSTRUCTURE
PHASE TRANSFORMATIONS
POLARIZATION
SILICON ALLOYS
SOLIDIFICATION
STRESSES
TENSILE PROPERTIES