Authors:
Motheo Sepako (1), Thuli Mkhaliphi (1), Deborah Blaine (2)
1- Department of Industrial Engineering, Stellenbosch University, South Africa
2- Department of Mechanical & Mechatronic Engineering, Stellenbosch University, South Africa
Abstract:
The study investigates the influence of Laser Powder Bed Fusion (LPBF) processing parameters on the production of AISI420 stainless steel (420SS). The research aims to determine the effect of energy density, a function of laser power, scan speed, layer height and hatching spacing on the density, porosity, microstructure, and mechanical properties of the as-built 420SS. The findings reveal that as built samples with a relative density exceeding 99% utilized volumetric energy density values ranging from 79.4 to 136.6 J/mm³ and laser power above 150 W. Samples featured porosity levels below 0.01%, characterized by isolated small spherical pores with diameters < 30 μm. The microstructure displayed retained austenite phases, with additional presence of martensite phases at the melt pool boundary, attributed to the rapid cooling associated with the LPBF process. The microhardness of the as-built samples exceeded 540 HV, surpassing that reported for cast 420SS.
DOI:
https://doi.org/10.59499/EP246281798
