TY - JOUR
T1 - Effect of additional magnesium on mechanical and high-cycle fatigue properties of 6061-T6 alloy
AU - Takahashi, Yoshimasa
AU - Shikama, Takahiro
AU - Nakamichi, Ryota
AU - Kawata, Yuji
AU - Kasagi, Naoki
AU - Nishioka, Hironari
AU - Kita, Syuzaburo
AU - Takuma, Masanori
AU - Noguchi, Hiroshi
N1 - Funding Information:
This study was financially supported in part by the Kansai University Grant-in-Aid for progress of research in graduate course ( 2012 ) and also by the Kansai University Expenditures for Support of Training Young Scholars ( 2013 ).
PY - 2015/8/2
Y1 - 2015/8/2
N2 - The effect of additional solute magnesium (Mg) on mechanical and high-cycle-fatigue properties of 6061-T6 aluminum alloy is investigated in detail. By adding 0.5% and 0.8% Mg to the 6061-T6 alloy with a normal stoichiometric Mg2Si composition (base alloy), the alloy exhibits eminent strain-aging characteristics demonstrated by the emergence of serrated flow, the negative strain-rate-sensitivity and relatively weakened temperature dependency of flow stress. The Mg-added new alloy also shows higher work-hardening rate than the base alloy particularly at initial flow regime and at lower strain rate. The S-N curve of the new alloy shows a clear fatigue limit which is absent in the base alloy. The fatigue limit of the new alloy is shown to be controlled by the threshold against small crack growth. Moreover, the new alloy clearly exhibits a coaxing phenomenon (time-dependent strengthening) which is absent in the base alloy. The coaxing effect is attributed to the existence of a small quasi-non-propagating crack whose growth resistance gradually increases during stress amplitude step-ups.
AB - The effect of additional solute magnesium (Mg) on mechanical and high-cycle-fatigue properties of 6061-T6 aluminum alloy is investigated in detail. By adding 0.5% and 0.8% Mg to the 6061-T6 alloy with a normal stoichiometric Mg2Si composition (base alloy), the alloy exhibits eminent strain-aging characteristics demonstrated by the emergence of serrated flow, the negative strain-rate-sensitivity and relatively weakened temperature dependency of flow stress. The Mg-added new alloy also shows higher work-hardening rate than the base alloy particularly at initial flow regime and at lower strain rate. The S-N curve of the new alloy shows a clear fatigue limit which is absent in the base alloy. The fatigue limit of the new alloy is shown to be controlled by the threshold against small crack growth. Moreover, the new alloy clearly exhibits a coaxing phenomenon (time-dependent strengthening) which is absent in the base alloy. The coaxing effect is attributed to the existence of a small quasi-non-propagating crack whose growth resistance gradually increases during stress amplitude step-ups.
UR - http://www.scopus.com/inward/record.url?scp=84933038164&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84933038164&partnerID=8YFLogxK
U2 - 10.1016/j.msea.2015.06.051
DO - 10.1016/j.msea.2015.06.051
M3 - Article
AN - SCOPUS:84933038164
VL - 641
SP - 263
EP - 273
JO - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
JF - Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing
SN - 0921-5093
ER -