Abnormal grain growth induced by <112̄0> orientation of AZ31 magnesium alloy

Abstract

The abnormal grain growth behaviour and preferential orientation of AZ31 Mg alloy were systematically examined. Abnormal grain growth was observed after annealing at 500°C for 9 h, and the grain growth rate was 1.3 mm h−1. Due to the abnormal grain growth, the activation energy of grain growth was reduced from 172 to 104 KJ mol−1. The abnormal grains with &lt;11 [Formula: see text] 0&gt; orientation grew preferentially, which resulted in the increase of the &lt;11 [Formula: see text] 0&gt; type texture intensity and the decrease of the &lt;0001&gt;. The energy difference of the misorientation is the main driving force for the formation of abnormal grains with &lt;11 [Formula: see text] 0&gt; orientation.

Austenite-Grain-Growth Kinetics and Mechanism in Type 347H Alloy Steel for Boiler Tubes

“…Another reason for the lower Qg for the present investigation is the AGG, which is in agreement with the literature [44]. Vasilyev and co-researchers (2019) have also studied the kinetics of grain growth in austenitic steels, and have reported a value of 79.7 kJ mol -1 in the temperature range of 1000-1200 o C for a complexly alloyed austenitic steel [45]. The higher Qg, in Vasilyev's study, can be explained for two reasons: (a) higher grain-boundary mobility at higher temperatures, and (b) complex alloying in the austenitic steel.…”