Unexpected Expansion Behavior of Mg-Al Alloys During Isothermal Ageing

A Unique Quenching and Deformation Dilatometer for Combined In Situ Neutron Diffraction Analysis of Engineering Materials

“…[37] The precipitation process can be either continuous or discontinuous, depending on aging temperature and Al content. [36,38] Since the density of β-phase precipitates is larger than that of pure Mg, it should be possible to observe a reduced length change in the TTL curve during the precipitation process. [38] At the same time, the occurrence of peaks from precipitates can also be observed in corresponding diffraction patterns.…”

“…[36,38] Since the density of β-phase precipitates is larger than that of pure Mg, it should be possible to observe a reduced length change in the TTL curve during the precipitation process. [38] At the same time, the occurrence of peaks from precipitates can also be observed in corresponding diffraction patterns. Due to the nanometer-sized β-phase precipitates and the phase detection limits (around 1 vol% of the phase) using in situ neutron diffraction technique, the information about the early stage of the precipitation process (nucleation) including the start point of precipitation at different aging temperatures might be lost in the continuously recorded neutron diffraction patterns.…”

“…[45] In addition to predicting the possible phase compositions, Thermo-Calc also provides additional thermodynamic information on the AlCrFeNiTi alloying system as follows: 1) The amount of phase fcc-L12#2 starts to decrease gradually at 750 C until it Reproduced under terms of the CC-BY license. [38] Copyright 2019, The Authors, published by JOM.…”

“…[ 37 ] The precipitation process can be either continuous or discontinuous, depending on aging temperature and Al content. [ 36,38 ]…”

“…Figure 6. Neutron diffraction patterns and temperature-length change curves of Mg-8.9Al during aging a,b) at 200 C, c,d) at 225 C, and e,f ) at 250 C.Reproduced under terms of the CC-BY license [38]. Copyright 2019, The Authors, published by JOM.…”