Research on dynamic precipitation behavior of pre-solution treated Mg–5 wt.% Zn–2 wt.% Al(–2 wt.%Y) alloy during creep

The creep tests of pre-solution treated Mg–5 wt.% Zn–2 wt.% Al(–2 wt.%Y) alloy are carried out at 175 °C under the load of 50 MPa, the interaction between dynamically precipitated MgZn2 (η) and basal plane dislocations is studied, research shows the dominant precipitate is MgZn2 transitional phase during 12 h creep period, and these [0 0 0 1]α rods bring about a strong pinning effect on basal plane slip system, screw dislocations on prismatic ( 0   1   1 ¯   0 ) α plane with a burgers vector of b = 1 3 [ 1   1   2 ¯   0 ] were observed under TEM. MgZn2 phase in Mg–5 wt.% Zn–2 wt.% Al–2 wt.%Y alloy is shorter and has a smaller inter space, the dynamic MgZn2 phase in two alloys was found to be established OR with the matrix: ( 1   1   2 ¯   0 ) η / / ( 0   0   0   2 ¯ ) α .