Heterogeneous microstructure and mechanical behaviour of Al-8.3Fe-1.3V-1.8Si alloy produced by laser powder bed fusion

Abstract

The relationship between processing parameters, microstructure, and mechanical properties of Al-8.3Fe-1.3V-1.8Si alloy processed by laser powder bed fusion is seldom studied. Therefore, fully dense alloys with two parameters were selected to investigate this key issue. The results show that the alloy with low power and scanning speed (S200) shows fan-shell-shaped melt pools and laser tracks while another (S350) shows a deeper and wider melt pool. Both alloys obtain a heterogeneous microstructure without a secondary phase in melt pool (MP) and a nano-sized phase in melt pool boundary (MPB). The difference between solid-solution strengthening and Orowan strengthening in MP and MPB contributes to the difference in compressive yield strength (S200: 380 ± 14 MPa and S350: 705 ± 16 MPa), and heterogeneous nano-hardness results in different crack behaviours and failure strains. This work indicates that adjusting processing parameters is an effective method to control microstructure and mechanical properties of this alloy.

Electrically/Magnetically Dual‐Driven Shape Memory Composites Fabricated by Multi‐Material Magnetic Field‐Assisted 4D Printing

“…The content of magnetic particles determines the saturation magnetization in the composites. [ 18a ] The act of external magnetic field on the magnetic particles polarize them, forming magnetic dipoles. [ 30 ] The presence of dipoles resulted in attraction among particles, consequently leading to the formation of magnetic chains and the reduction of inter‐particle distances.…”

“…The stiffness and hardness in the aligned direction were increased by 29% and 23% compared with the vertical direction, respectively. It also demonstrated that MF‐DLP 4D printing technique could significantly improve the wear resistance and magnetic stimuli‐response behavior of magnetic composites in the aligned direction, [ 18 ] showing effective enhancement of functionality through manipulation of the magnetic particles during 4D printing. Some challenges remain on the MF‐DLP fabricated smart materials by remote control of the actuators using electrical and magnetic fields simultaneously or sequentially.…”

Effects of laying angles on stainless steel fabricated by selective laser melting

“…For example, Xie et al 19 reported that befitting overlap region widths (ORWs) could improve the densification degree and guarantee metallurgical quality. Yu et al 20 demonstrated that the microstructure and mechanical properties of SLM-built alloy can be effectively controlled by adjusting processing parameters. Gatta et al 21 identified that the feasibility of the SLM process that fabricated a customised Al–Cu–Mg–Si alloy, and the optimised process parameters can obtain the maximum relative density of 97%.…”