“Influence of Si, Sb and Sr Additions on the Microstructure ...

Chapter 4: Results <strong>and</strong> Discussion
difference in strain rate makes deformation mode different in two cases. Superior
creep behavior <strong>of</strong> 0.5% <strong>Si</strong> added alloy over 0.2% <strong>Si</strong> added alloy is attributed to the
high work hardening effect in 0.5% <strong>Si</strong> added alloy, which is due to the presence <strong>of</strong>
higher volume <strong>of</strong> Mg2<strong>Si</strong> precipitates.
9
8
7
6
3
2
1
0
16
14 1
12
10
8
6
4 1
2 1
Secondary creep rate I
5.0239 x 10'“ ".4, n '“
Creep extension
8.29 °.»'o
Secondary stage Ternary $139?
Primary stage
_.fl
Creep life
5817 h
Secondary Creep rate
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0 1000 2000 3000 4000 5000 6000
I­
' Secondary creep rate
- 4.171 x 10" %n"
.. Creep extension
_ 14.306 %
i Creep life
131.15 h
an