Anisotropic and temperature-dependent growth mechanism of S-phase precipitates in Al-Cu-Mg alloy in relation with GPB zones

TY - JOUR

T1 - Anisotropic and temperature-dependent growth mechanism of S-phase precipitates in Al-Cu-Mg alloy in relation with GPB zones

AU - Yin, Mei Jie

AU - Chen, Jiang Hua

AU - Wang, Shuang Bao

AU - Liu, Zi Ran

AU - Cha, Li Mei

AU - Duan, Shi Yun

AU - Wu, Cui Lan

N1 - Publisher Copyright: © 2016 The Nonferrous Metals Society of China.

PY - 2016/1/1

Y1 - 2016/1/1

N2 - By employing atomic-resolution imaging and first principles energy calculations, the growth behavior of S-phase precipitates in a high strength Al-Cu-Mg alloy was investigated. It is demonstrated that the nucleation and growth of the S-phase precipitate are rather anisotropic and temperature-dependent companying with low dimensional phase transformation. There are actually two types of Guinier-Preston (GP) zones that determine the formation mechanism of S-phase at high aging temperatures higher than 180 °C. One is the precursors of the S-phase itself, the other is the structural units or the precursors of the well-known Guinier-Preston-Bagaryatsky (GPB) zones. At high temperatures the later GPB zone units may form around S-phase precipitate and cease its growth in the width direction, leading to the formation of rod-like S-phase crystals; whereas at low temperatures the S-phase precipitates develop without the interference with GPB zones, resulting in S-phase precipitates with lath-like morphology.

AB - By employing atomic-resolution imaging and first principles energy calculations, the growth behavior of S-phase precipitates in a high strength Al-Cu-Mg alloy was investigated. It is demonstrated that the nucleation and growth of the S-phase precipitate are rather anisotropic and temperature-dependent companying with low dimensional phase transformation. There are actually two types of Guinier-Preston (GP) zones that determine the formation mechanism of S-phase at high aging temperatures higher than 180 °C. One is the precursors of the S-phase itself, the other is the structural units or the precursors of the well-known Guinier-Preston-Bagaryatsky (GPB) zones. At high temperatures the later GPB zone units may form around S-phase precipitate and cease its growth in the width direction, leading to the formation of rod-like S-phase crystals; whereas at low temperatures the S-phase precipitates develop without the interference with GPB zones, resulting in S-phase precipitates with lath-like morphology.

KW - age hardening

KW - aluminum alloy

KW - anisotropy

KW - crystal growth

KW - precipitation

UR - http://www.scopus.com/inward/record.url?scp=84958252524&partnerID=8YFLogxK

U2 - 10.1016/S1003-6326(16)64082-7

DO - 10.1016/S1003-6326(16)64082-7

M3 - 文章

AN - SCOPUS:84958252524

SN - 1003-6326

VL - 26

SP - 1

EP - 11

JO - Transactions of Nonferrous Metals Society of China

JF - Transactions of Nonferrous Metals Society of China

IS - 1

ER -