Film rupture and partial wetting over flat surfaces with variable distributor width
Journal article
Authors/Editors
Strategic Research Themes
No matching items found.
Publication Details
Author list: Giannetti N., Trinuruk P., Yamaguchi S., Saito K.
Publisher: Springer
Publication year: 2019
Journal: Metallurgical and Materials Transactions A (1073-5623)
Volume number: 25
Issue number: 10
Start page: 1313
End page: 1324
Number of pages: 12
ISSN: 1073-5623
eISSN: 1543-1940
Languages: English-Great Britain (EN-GB)
View in Web of Science | View on publisher site | View citing articles in Web of Science
Abstract
Aluminum piston alloys of the AA4032 type are produced by direct-chill (DC) casting and subsequent forging; therefore, it is important to understand their thermomechanical behavior. In recent years, it was shown that additions of Cu and Er could improve mechanical properties of these alloys at room and high temperatures. In this work, we studied the constitutive behavior of AA4032-type alloys with and without Cu and Er additions. The experimental true stress–true strain curves were obtained by compression tests under various temperatures [683 K to 723 K (410 °C to 450 °C)] and strain rates (0.01 to 10 s−1) to determine constitutive parameters [strain-rate sensitivity, activation energy, and Zener–Hollomon (Z) parameter] for the hot deformation behavior of AA4032-type piston alloys with and without additions of Cu and Er. The flow stress decreased with increasing deformation temperature and decreasing strain rate. The results also showed that increasing the Cu content increased the flow stress over the applied range of deformation conditions due to solid-solution strengthening and the formation of primary Si particles, which led to an increase in the activation energy during hot deformation. Moreover, the main microstructural damage in the AA4032 alloy with 3.5 pct Cu was predominantly due to the cracking of primary Si particles. Additions of 0.4 pct Er and 3.5 pct Cu lower the activation energy of deformation, Q, as compared to the base alloy and the alloy with 3.5 pct Cu. The microstructures in the deformed specimens consisted of subgrains, recrystallized grains, and fine eutectic phases. The alloys containing Er demonstrated more polygonized grains at a low strain rate than the alloys without Er, indicating that Er hindered recrystallization development. The peak stress of the AA4032 alloy with 3.5 pct Cu alloy was higher than for the base AA4032 alloy and for the AA4032 alloy with 3.5 pct Cu and 0.4 pct Er additions, which was attributed to the prevalence of the work-hardening mechanism over the softening mechanism. © 2019, The Author(s).
Keywords
No matching items found.
Contact Information