Microstructure and properties of additively manufactured Al–Ce–Mg alloys

Abstract

Additive manufacturing of aluminum alloys is largely dominated by a near-eutectic Al-Si compositions, which are highly weldable, but have mechanical properties that are not competitive with conventional wrought Al alloys. In addition, there is a need for new Al alloys with improved high temperature properties and thermal stability for applications in the automotive and aerospace fields. In this work, we considered laser powder bed fusion additive manufacturing of two alloys in the Al–Ce–Mg system, designed as near-eutectic (Al–11Ce–7Mg) and hyper-eutectic (Al–15Ce–9Mg) compositions with respect to the binary L → Al + Al11Ce eutectic reaction. The addition of magnesium is used to promote solid solution strengthening. A custom laser scan pattern was used to reduce the formation of keyhole porosity, which was caused by excessive vaporization due to the high vapor pressure of magnesium. The microstructure and tensile mechanical properties of the alloys were characterized in the as-fabricated condition and following hot isostatic pressing. The two alloys exhibit significant variations in solidification structure morphology. These variations in non-equilibrium solidification structure were rationalized using a combination of thermodynamic and thermal modeling. Both alloys showed higher yield strength than AM Al-10Si-Mg for temperatures up to 350 °C and better strength retention at elevated temperatures than additively manufactured Scalmaloy.

Additive manufacturing of an ultrastrong, deformable Al alloy with nanoscale intermetallics

“…Similar effects have been reported for Al alloys with the aid of nucleants, such as Al 3 Zr 18 – 20 , Al 3 Sc 21 , 22 , Al 3 Ti 37 , TiB 2 14 – 17 , for the refinement of grain size of Al matrix. The rosette structure was reported in other Al alloys where Ce and Mn were introduced for precipitate strengthening, yet the resultant deformation mechanisms remain unexplored 38 – 41 .…”

Recent Advancements in Material Waste Recycling: Conventional, Direct Conversion, and Additive Manufacturing Techniques

“…Commonly used 3D printing processes for stainless steel alloys, aluminum alloys, titanium alloys, and super alloys are laser powder bed fusion (LPBF) [75][76][77][78][79][80][81][82][83] wire arc direct energy deposition [84][85][86], laser metal deposition [87,88], and additive friction stir deposition [89][90][91] processes. The current research in additive manufacturing on aluminum alloys [92][93][94][95][96][97][98][99][100][101][102][103], stainless steel [104][105][106][107], titanium alloys [108][109][110][111][112][113][114][115][116], and nickel-based super alloys [117][118][119][120] aims at improving the microstructure and mechanical properties of materials by reducing the defects…”

Surface Defect Mitigation of Additively Manufactured Parts Using Surfactant-Mediated Electroless Nickel Coatings

“…In addition, posttreatment methods [9] such as hot isostatic pressing (HIP), a technique that involves the simultaneous application of both high temperature and pressure (isostatic) to collapse and diffusion-bond internal pores in a structure, have been employed for densification and bulk porosity reduction. However, this approach suffers from lowering the ductility of the AM parts as well as damaging their stress rupture response [10,11]. Properties such as ductility and stress response are important in the automotive and aerospace industries, in conjunction with a requirement for substantial anticorrosive behaviour and fatigue resistance [1,12,13].…”