Effect of Compound Fields of Ultrasonic Vibration and Applied Pressure on the 3D Microstructure and Tensile Properties of Recycled Al-Cu-Mn-Fe-Si Alloys

Abstract

The effect of compound fields of ultrasonic vibration and applied pressure (UV+AP) on three-dimensional (3D) microstructure and tensile properties of recycled Al-Cu-Mn-Fe-Si alloys was systematically studied using conventional two-dimensional (2D) microscopy, synchrotron X-ray tomography, and tensile test. The properties of UV+AP treated alloys with the pouring temperature of 740, 710 and 680 °C were compared when those alloys achieved after gravity casting. After UV+AP treatment, the alloy with pouring temperature of 710 °C show the smallest grain size. Also, the sizes of Fe-rich phases and Al2Cu are greatly reduced and their 3D morphologies are compacted. The mechanical properties of UV+AP treated alloys are relatively higher than those measured for gravity cast equivalents. This improvement can be explained by the synergistic effect of acoustic cavitation, acoustic streaming, and force-feeding, which resulted in the dendrite fragmentation, uniform solute distribution, and microstructural refinement. The Orowan strengthening and solution strengthening were identified as the main strengthening mechanisms.

Multiscale characterization of the nucleation and 3D structure of Al3Sc phases using electron microscopy and synchrotron X-ray tomography

“…The synchrotron X-ray tomography experiment was carried out at beamline ID 19 of the European Synchrotron Radiation Facility (ESRF), France. The samples were machined into ~1 mm diameter rod, and the detailed sample preparation procedure can be found in [24][25][26][27]. The parameters used for the tomography acquisition were Journal Pre-proof J o u r n a l P r e -p r o o f 6 summarized in Table 1.…”

Effect of Ultrasonic Vibration and Interpass Temperature on Microstructure and Mechanical Properties of Cu-8Al-2Ni-2Fe-2Mn Alloy Fabricated by Wire Arc Additive Manufacturing

“…Hence, we can predict that the temperature of the arc melting pool is high enough to re-melt the equiaxed dendrites region (Figure 4a), while the SDAs help to maintain the growth direction of primary dendrites in subsequent layers (Figures 3a1-b4 and 4f), and finally forms the epitaxial growth. Previous studies reveal that the microstructure of materials depends on both the nucleation condition and subsequent growth stage [19,26]. The UVA treatment WAAM at lower interpass temperature can hinder the growth of epitaxial columnar more effectively and promote the formation of new grains.…”

“…Eventually, WAAM parts with refined grains are obtained UVA treatment at a lower interpass temperature process during the nucleation stage. Previous studies reveal that the microstructure of materials depends on both the nucleation condition and subsequent growth stage [19,26]. The UVA treatment WAAM at lower interpass temperature can hinder the growth of epitaxial columnar more effectively and promote the formation of new grains.…”

“…The acoustic nonlinear effects (including specific cavitation and acoustic streaming) arising in ultrasonic vibration can influence the convection and solidification behaviors of the molten pool [18]. Hence, ultrasonic vibration has been effectively used in melting metal solidification processes such as casting [19,20], welding [21], cladding [22], additive manufacturing [23][24][25][26]. Wang et al [25] discovered that laser engineered net shaping of Inconel 718 with ultrasonic vibration could refine the microstructure, decrease micropore, improve homogeneity of chemical contents and shorten the size of Laves phases.…”

Effects of Continuous and Pulsed Ultrasonic Treatment on Microstructure and Microhardness in Different Vertical Depth of ZL205A Castings

“…Segregation structure seriously reduced the uniformity of castings, and would not be improved after homogenizing annealing, even separating out a heterogeneous sediment lead to stress concentration and crack initiation. Those have a great impact on mechanical properties, corrosion resistance, physical properties, and castability of ZL205A alloy [ 7 , 8 , 9 , 10 ].…”