Intermetallic phase evolution and strengthening effect in Al-Mg2Si alloys with different Cu/Ni ratios

Authors

Yilin Sun, Tianjin University
Chong Li, Tianjin University
Yongchang Liu, Tianjin University
Liming Yu, Tianjin University
Hui Jun Li, University of WollongongFollow

RIS ID

118420

Publication Details

Sun, Y., Li, C., Liu, Y., Yu, L. & Li, H. (2018). Intermetallic phase evolution and strengthening effect in Al-Mg2Si alloys with different Cu/Ni ratios. Materials Letters, 215 254-258.

Abstract

Microalloying of an Al–15%Mg₂Si alloy (wt%) with Ni and Cu produced an enhanced strengthening response, increasing hardness whilst also improving tensile strength due to the formation and evolution of intermetallic phases. With the increase of Cu/Ni ratios, intermetallic phases translate from Al₃Ni or Al₃CuNi to Al₇Cu₄Ni, and the total volume fraction of Al₃CuNi and Al₇Cu₄Ni increases to 3.51% (1%Ni and 5%Cu, Cu/Ni ratio = 5). The thermally stable Al₃CuNi and Al₇Cu₄Ni phases are connected to each other forming chains and tend to build up a network. As a result, the ultimate tensile strength (at 350 °C) of the alloy (Cu/Ni ratio = 5) reached up to 132 MPa, 131.6% higher than that of Al–15%Mg₂Si alloy.