Unveiling the influence of dendrite characteristics on the slip/twinning activity and the strain hardening capacity of Mg-Sn-Li-Zn cast alloys

Microstructure evaluation and thermal deformation behaviours of wrought magnesium alloys

“…The true stress–strain flow curves at low temperature (473 and 523 K) show a decreasing hardening law of rapid initial hardening, steady hardening rate, peak flow stress and gradual continuous dynamic softening. It is generally believed that the continuous softening behaviour of as-cast microstructure is related to the dynamic fragmentation of the initial microstructure [34]. The hardening rate curve in Figure 7(e) shows that basal plane slip and twins nucleation/propagation harmonise the internal strains during the initial plastic deformation (stage I), accompanied by a continuous decreasing hardening rate.…”

“…The characteristic sigmoidal profiles are observed while the alloys deform at lower temperatures. For instance, as shown in Figure 7(b), with the deformation rate of 0.1 s −1 , the sigmoidal profiles have maintained from 473 until to 623 K. However, the characters are disappeared in the curves while the thermal deformation temperature is up to 673 K, which can be attributed to activation of the pyramidal slip system [34,35]. Twinning and pyramidal <c + a> slip systems are two competitors for coordinating basal slip of hcp crystals during thermal deformation.…”

“…This may cause an increase in the hardening rate, which is correlated with the reported sigmoidal profiles of the stage I curves. In essence, this profile is mainly attributed to the activation energy of the non-basal slip system [34]. With the initial grain fragmentation and increasing recrystallisation fraction, the hardening rate gradually decreases to the balance of hardening and dynamic softening (stage III).…”

Twinning Behavior, Microstructure Evolution and Mechanical Property of Random-Orientated ZK60 Mg Alloy Compressed at Room Temperature

“…In previous studies, it has been found that there are many factors affecting the twinning behavior of Mg alloys, such as temperature [ 16 ], alloy composition [ 17 , 18 , 19 ], strain [ 20 ], etc. Therefore, we need a lot of systematic research to regulate the twinning behavior in Mg alloys [ 21 ].…”

Investigations on the WEDM of Friction Stir Processed Magnesium/Graphene-Boron Nitride Hybrid Surface Composite through the Entropy-COPRAS Approach

“…However, these materials have some major limitations, such as low creep, sti ness, low resistance to wear, and increased reactivity towards chemicals that frequently limit their industrial applications. It also has poor ductility, characterized by a brittle-like performance at ambient temperature owing to its HCP crystal structure and a limited slip system [3][4][5]. Composite development is considered one of the key ways to enhance the desired strength of Mg matrix material by the addition of selected reinforcements.…”