Microstructural Modification of LPBF-Processed High Manganese Steel by Laser Parameter Alternation

Microstructural Modification of LPBF-Processed High Manganese Steel by Laser Parameter Alternation

Abstrakt

The presented study investigates the influence of laser-based process parameters on the character of microstructure in high manganese steel X30Mn22 fabricated by laser powder bed fusion. It has already been shown by several studies that the local thermal gradient modification achieved by processing parameter alternation can lead to distinctively different microstructures. The aim of this study was to utilize this phenomenon as a design tool for obtaining solidification microstructures with various characteristics in terms of crystallographic texture and/or grain boundary character. Based on the singletrack analysis in wide range of laser power – laser scanning speed combinations, the optimal parameters have been selected for test cube fabrication and subsequently for tensile specimens. It has been found that significant differences in meltpool shape can be achieved and that such variety is reflected in character of as-built microstructure. Depending on the meltpool shape, a fibre structure with fine microstructure or distinct cube texture was achieved. Such variation in microstructural character led to notable differences in elastic moduli indicating various mechanical properties. The results of this study suggest a viable possibility to intentionally modify microstructure with the goal to alter elastic and plastic behaviour of fabricated material.

The presented study investigates the influence of laser-based process parameters on the character of microstructure in high manganese steel X30Mn22 fabricated by laser powder bed fusion. It has already been shown by several studies that the local thermal gradient modification achieved by processing parameter alternation can lead to distinctively different microstructures. The aim of this study was to utilize this phenomenon as a design tool for obtaining solidification microstructures with various characteristics in terms of crystallographic texture and/or grain boundary character. Based on the singletrack analysis in wide range of laser power – laser scanning speed combinations, the optimal parameters have been selected for test cube fabrication and subsequently for tensile specimens. It has been found that significant differences in meltpool shape can be achieved and that such variety is reflected in character of as-built microstructure. Depending on the meltpool shape, a fibre structure with fine microstructure or distinct cube texture was achieved. Such variation in microstructural character led to notable differences in elastic moduli indicating various mechanical properties. The results of this study suggest a viable possibility to intentionally modify microstructure with the goal to alter elastic and plastic behaviour of fabricated material.

laser powder bed fusion; LPBF; X30Mn22; high-manganese steel; microstructure modification

laser powder bed fusion; LPBF; X30Mn22; high-manganese steel; microstructure modification

FÁBRY, A.; KOUTNÝ, D.; ŠMÍD, M.

07.10.2025

ASTM

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https://icam2025.amcoe.org/event/d807440e-72cb-4782-931d-5021c4582163/program