Replies to post #2602 on Arcam AB fka AMAVF

[charlie T colton]

Different high-entropy alloy, different research.

The AlCoCrFeNi alloy was produced with an Arcam A2X at the Institute for Materials Research, Tohoku University, Japan.

First demonstration of promising selective electron beam melting method for utilizing high-entropy alloys as engineering materials

[I]High-entropy alloys (HEAs) are equiatomic, multi-element systems that contain five or more principal elements and have unique and excellent properties. However, it is difficult to overcome the inherent complexity and high levels of control required to produce homogeneous alloys industrially using a conventional casting method. We applied an additive manufacturing technique involving the use of selective electron beam melting (SEBM), which can facilitate a high level of local process control and generate rapid solidification cooling rates.
The mechanical properties of the equiatomic AlCoCrFeNi HEA molds produced by SEBM were far superior to those of the corresponding castings. The ductility in particular was remarkably improved. The fracture strength was above 1400 MPa, which was more than six times higher than that of SUS304, a conventional engineering material. We succeeded in demonstrating for the first time that SEBM is a promising manufacturing process for utilizing HEAs as engineering materials.

The SUS304 is a grade of stainless steel.


The Novel Low-Density, High-Hardness, High-entropy Alloy with Close-packed Single-phase Nanocrystalline Structures research was a combined effort from North Carolina State University and Qatar University.

A low-density, nanocrystalline high-entropy alloy, Al20Li20Mg10Sc20Ti30 was produced by mechanical alloying. It formed a single-phase fcc structure during ball milling and transformed to single-phase hcp upon annealing. The alloy has an estimated strength-to-weight ratio that is significantly higher than other nanocrystalline alloys and is comparable to ceramics. High hardness is retained after annealing.

They emphasized that this was a very low density alloy. I couldn't find what the density of the AlCoCrFeNi alloy was.