TY - JOUR
T1 - Precipitation sequence in friction stir weld of 6063 aluminum during aging
AU - Sato, Yutaka S.
AU - Kokawa, Hiroyuki
AU - Enomoto, Masatoshi
AU - Jogan, Shigetoshi
AU - Hashimoto, Takenori
N1 - Funding Information:
The authors are grateful to Messrs. Yoshihiro Ohsawa and Akira Honda for technical assistance. They thank Dr. Tomiyoshi Kanai and Mr. Shoichi Sato for useful advice. Financial support from the Japanese Ministry of Education, Science, Sports and Culture with a Grant-in-Aid for Scientific Research is gratefully acknowledged.
PY - 1999
Y1 - 1999
N2 - The precipitation sequence in friction stir weld of 6063 aluminum during postweld aging, associated with Vickers hardness profiles, has been examined by transmission electron microscopy. Friction stir welding produces a softened region in the weld, which is characterized by dissolution and growth of the precipitates. The precipitate-dissolved region contains a minimum hardness region in the as-welded condition. In the precipitate-dissolved region, postweld aging markedly increases the density of strengthening precipitates and leads to a large increase in hardness. On the other hand, aging forms few new precipitates in the precipitate-coarsened region, which shows a slight increase in hardness. The postweld aging at 443 K for 43.2 ks (12 hours) gives greater hardness in the overall weld than in the as-received base material and shifts the minimum hardness from the as-welded minimum hardness region to the precipitate-coarsened region. These hardness changes are consistent with the subsequent precipitation behavior during postweld aging. The postweld solution heat treatment (SHT) and aging achieve a high density of strengthening precipitates and bring a high hardness homogeneously in the overall weld.
AB - The precipitation sequence in friction stir weld of 6063 aluminum during postweld aging, associated with Vickers hardness profiles, has been examined by transmission electron microscopy. Friction stir welding produces a softened region in the weld, which is characterized by dissolution and growth of the precipitates. The precipitate-dissolved region contains a minimum hardness region in the as-welded condition. In the precipitate-dissolved region, postweld aging markedly increases the density of strengthening precipitates and leads to a large increase in hardness. On the other hand, aging forms few new precipitates in the precipitate-coarsened region, which shows a slight increase in hardness. The postweld aging at 443 K for 43.2 ks (12 hours) gives greater hardness in the overall weld than in the as-received base material and shifts the minimum hardness from the as-welded minimum hardness region to the precipitate-coarsened region. These hardness changes are consistent with the subsequent precipitation behavior during postweld aging. The postweld solution heat treatment (SHT) and aging achieve a high density of strengthening precipitates and bring a high hardness homogeneously in the overall weld.
UR - http://www.scopus.com/inward/record.url?scp=0033316602&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033316602&partnerID=8YFLogxK
U2 - 10.1007/s11661-999-0223-5
DO - 10.1007/s11661-999-0223-5
M3 - Article
AN - SCOPUS:0033316602
SN - 1073-5623
VL - 30
SP - 3125
EP - 3130
JO - Metallurgical Transactions A (Physical Metallurgy and Materials Science)
JF - Metallurgical Transactions A (Physical Metallurgy and Materials Science)
IS - 12
ER -