Excellent mechanical properties of Al-Mn-Sc alloyThe enhanced mechanical properties of laser powder bed fusion Al-Mn-Sc alloy via non-isothermal aging
Conclusions
In this paper, the LPBF Al-Mn-Sc alloys with excellent mechanical properties were obtained by using a novel non-isothermal thermal treatment at a heating rate of 2 °C/min from 30°C to 350°C. By analysing precipitation behaviour and mechanical properties, the conclusions are as follows:
(1) By analysing the activation energies and Avrami exponent of Al-Sc and Al-Mn precipitates, it was found that the precipitation of Al3(Sc,Zr) after nonisothermal aging was mainly dominated by interface-controlled growth through the reaction at the interface of matrix/particle, whereas the phase transformation of Al-Mn precipitates was mainly dominated by diffusion-driven phase transition. The non-isothermal model proposed was well suited for predicting non-isothermal processes of LPBF AlMn-Sc alloy.
(2) More nanoscale Al3(Sc,Zr) precipitated within the grain after non-isothermal aging. The precipitates QC-Al81Mn19 precipitated along the grain boundaries for as-built samples, whereas they transformed into coarser precipitates QC Al85(Mn0.72Fe0.28)14Si, Al4Mn and Al6Fe0.5Mn0.5 after non-isothermal aging.
(3) The excellent mechanical properties of LPBF Al-MnSc alloy are obtained by non-isothermal aging, which is equivalent to or even better than those obtained by isothermal aging. By revealing the strengthening mechanism, it is found that the excellent mechanical properties of the non-isothermally aged Al-Mn-Sc alloys are mainly attributed to the retention of the solid solution strengthening and fine grains by the highly efficient heat treatment, and the precipitation strengthening of the precipitates Al3(Sc,Zr), Al81Mn19, Al85(Mn0.72Fe0.28)14Si, Al4Mn and Al6Fe0.5Mn0.5
Jiang, W., Deng, Y., Xu, X., He, X., & Sing, S. L. (2024). The enhanced mechanical properties of laser powder bed fusion Al-Mn-Sc alloy via non-isothermal aging. Virtual and Physical Prototyping, 19(1). https://doi.org/10.1080/17452759.2024.2317777
https://www.researchgate.net/publication/378401163_The_enhanced_mechanical_properties_of_laser_powder_bed_fusion_Al-Mn-Sc_alloy_via_non-isothermal_aging