Effects of Laser Power and Scanning Speed on the Microstructural Evolution and Hardness of AlCrFeNiMn HEAs Fabricated via Laser Cladding

Abstract:

High entropy alloys (HEAs) are a novel type of material with distinct features caused by their atypical compositions. However, their microstructure and mechanical qualities are greatly dependent on processing parameters. Laser cladding is a versatile method for producing HEA coatings, but optimizing the process to achieve the required microstructure and hardness remains a difficulty. Therefore, this work analyses the impact of laser processing parameters, especially laser power and scan speed, on the microstructure and hardness of AlCrFeNiMn HEAs manufactured via laser cladding. The AlCrFeNiMn HEA was successfully created utilizing the laser metal deposition process and several analyses were conducted. Columnar grains were discovered on alloy samples produced with 1500W laser power. As the laser power rose to 2200W coarse columnar dendritic microstructures were discovered. Samples processed with 2400W laser power showed the fewest visible fractures with an increase in scanning speed. As the laser power increased, the hardness of samples decreased from 427 Hv to 382 Hv.

• Periodical: Key Engineering Materials (Volume 1014)
• Pages: 3-9
• DOI: https://doi.org/10.4028/p-UVwR6c
• Online since: June 2025
• Authors: Praise Mpofu*, Nicholas Malatji, Mxolisi Brendon Shongwe, Lehlogonolo Rudolf Kanyane
• Keywords: High Entropy Alloys, Laser Power, Laser Speed, Microstructure

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