کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1446199 | 988601 | 2013 | 14 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Lattice misfit during ageing of a polycrystalline nickel-base superalloy Lattice misfit during ageing of a polycrystalline nickel-base superalloy](/preview/png/1446199.png)
The temporal evolution of the lattice parameters and lattice misfit of an advanced polycrystalline nickel-base superalloy have been studied in situ during an ageing heat treatment using synchrotron X-ray diffraction. During ageing, the γ and γ′ lattice parameters were both observed to decrease, a trend that cannot be attributed to a loss of coherency alone. Phase-extracted γ′ replicated this behaviour. Atom probe tomography was used to measure the compositional changes between the start and end of the ageing heat treatment. Using these data, a thermodynamic assessment was made using the software ThermoCalc of the structural change across the interface between γ and γ′. Subsequently, the unconstrained lattice parameters were estimated and were shown to be in good agreement with the X-ray diffraction measurements. Thus, the observed anomalous lattice misfit behaviour was concluded to be dominated by elemental exchange between the γ and γ′ phases during ageing.
Journal: Acta Materialia - Volume 61, Issue 20, December 2013, Pages 7791–7804