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Title: Effect of heat treatments on mechanical properties and damage evolution of thixoformed aluminium alloys

Abstract

In the present work, the effects of heat treatments on mechanical properties, microstructure evolution and damage resulting from plastic deformation of thixoformed A319 and A356 aluminium alloys, are studied. The thixoforming process can lead to the production of components that are characterized by very good mechanical properties and low porosity with a globular microstructure which is fine and uniform. The mechanical properties can be further improved through heat treatments such as T5 and T6. The prime factor influencing the damage in the alloys belonging to the Al-Si system is represented by decohesion of silicon particles resulting from the stress concentration at the particle-matrix interfaces. A statistical analysis of fractured particles after tensile tests in the as-cast and as-treated condition has been carried out in the present work; optical and scanning electron microscopy techniques have been used to characterize the microstructure and fracture surfaces of the specimens and the results are fully presented.

Authors:
 [1];  [2];  [2]
  1. INFM-Dept. of Ingegneria dell'Innovazione, Engineering Faculty, University of Lecce, Via per Arnesano, I-73100-Lecce (Italy). E-mail: pasquale.cavaliere@unile.it
  2. INFM-Dept. of Ingegneria dell'Innovazione, Engineering Faculty, University of Lecce, Via per Arnesano, I-73100-Lecce (Italy)
Publication Date:
OSTI Identifier:
20748756
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 55; Journal Issue: 1; Other Information: DOI: 10.1016/j.matchar.2005.02.006; PII: S1044-5803(05)00081-1; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM ALLOYS; DAMAGE; FRACTURES; HEAT TREATMENTS; INTERFACES; MICROSTRUCTURE; PARTICLES; PLASTICITY; POROSITY; SCANNING ELECTRON MICROSCOPY; SILICON; STRESSES; SURFACES

Citation Formats

Cavaliere, P., Cerri, E., and Leo, P. Effect of heat treatments on mechanical properties and damage evolution of thixoformed aluminium alloys. United States: N. p., 2005. Web. doi:10.1016/j.matchar.2005.02.006.
Cavaliere, P., Cerri, E., & Leo, P. Effect of heat treatments on mechanical properties and damage evolution of thixoformed aluminium alloys. United States. doi:10.1016/j.matchar.2005.02.006.
Cavaliere, P., Cerri, E., and Leo, P. 2005. "Effect of heat treatments on mechanical properties and damage evolution of thixoformed aluminium alloys". United States. doi:10.1016/j.matchar.2005.02.006.
@article{osti_20748756,
title = {Effect of heat treatments on mechanical properties and damage evolution of thixoformed aluminium alloys},
author = {Cavaliere, P. and Cerri, E. and Leo, P.},
abstractNote = {In the present work, the effects of heat treatments on mechanical properties, microstructure evolution and damage resulting from plastic deformation of thixoformed A319 and A356 aluminium alloys, are studied. The thixoforming process can lead to the production of components that are characterized by very good mechanical properties and low porosity with a globular microstructure which is fine and uniform. The mechanical properties can be further improved through heat treatments such as T5 and T6. The prime factor influencing the damage in the alloys belonging to the Al-Si system is represented by decohesion of silicon particles resulting from the stress concentration at the particle-matrix interfaces. A statistical analysis of fractured particles after tensile tests in the as-cast and as-treated condition has been carried out in the present work; optical and scanning electron microscopy techniques have been used to characterize the microstructure and fracture surfaces of the specimens and the results are fully presented.},
doi = {10.1016/j.matchar.2005.02.006},
journal = {Materials Characterization},
number = 1,
volume = 55,
place = {United States},
year = 2005,
month = 7
}
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