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1770349 
Journal Article 
Tensile and fatigue properties of a cast aluminum alloy with Ti, Zr and V additions 
Elhadari, HA; Patel, HA; Chen, DL; Kasprzak, W 
2011 
1 
Materials Science and Engineering A: Structural Materials Properties Microstructure and Processing
ISSN: 0921-5093
EISSN: 1873-4936 
528 
28 
8128-8138 
WOS:000295555500012 
The development of aluminum alloys for automotive
powertrain applications is in high demand due to the required weight reduction and fuel
efficiency. The aim of this study was to evaluate the microstructure and mechanical properties of
a newly developed Al-7%Si-1%Cu-0.5%Mg cast alloy with further additions of Ti, Zr and V. The
microstructure of the alloys consisted of Al dendrites surrounded by Al-Si eutectic structures
with Mg/Cu/Fe-containing Si particles, and contained nano-sized trialuminide precipitates in the
Ti/Zr/V added alloys. The alloys had a significantly (60-87%) higher yield strength but lower
ductility than A356-T6 and 319-T6 alloys. With the addition of Ti/Zr/V both monotonic and cyclic
yield strengths increased, but ductility and hardening capacity decreased due to reduced
dislocation storage capacity caused by stronger interactions between dislocations and
trialuminide precipitates. The Zr/V-modified alloy had a longer fatigue life, and all the alloys
exhibited cyclic stabilization at low strain amplitudes and cyclic hardening at higher strain
amplitudes. With increasing strain amplitude, the extent of cyclic hardening increased. Both
cyclic yield strength and cyclic strain hardening exponent were higher than the corresponding
monotonic yield strength and strain hardening exponent, indicating that a stronger cyclic
hardening ability of the alloys developed. Fatigue cracks were observed to initiate at near-
surface defects, and crack propagation was mainly characterized by the formation of fatigue
striations together with secondary cracks. (C) 2011 Elsevier B.V. All rights reserved. 
Cast aluminum alloy; Heat treatment; Microstructure; Tensile properties; Low cycle fatigue; Cyclic hardening