Microstructure and tribological response of selective laser melted AISI 316L stainless steel : the role of severe surface deformation

Kumar, Vikesh and Joshi, Manoj D. and Pruncu, Catalin and Singh, Indrasen and Hosmani, Santosh S. (2021) Microstructure and tribological response of selective laser melted AISI 316L stainless steel : the role of severe surface deformation. Journal of Materials Engineering and Performance. ISSN 1059-9495

[thumbnail of Kumar-etal-JMEP-2021-MIcrostructure-and-tribological-response-of-selective-laser-melted-AISI-316L] Text (Kumar-etal-JMEP-2021-MIcrostructure-and-tribological-response-of-selective-laser-melted-AISI-316L)
Kumar_etal_JMEP_2021_MIcrostructure_and_tribological_response_of_selective_laser_melted_AISI_316L.pdf
Accepted Author Manuscript
Restricted to Repository staff only until 12 April 2022.

Download (8MB) | Request a copy from the Strathclyde author

    Abstract

    This study investigates the effect of surface mechanical attrition treatment (SMAT) (a severe surface-deformation process) on microstructure and tribological behavior of AISI 316L steel samples manufactured using the selective laser melting (SLM) technique. The specimens are built in different directions (0°, 45°, and 90°). The microstructure of annealed SLM samples shows the non-uniform distribution and random orientation of grains. It contains high-angle grain boundaries and a high density of dislocations. The average grain size is about 63, 51, and 41 μm for 0°, 45°, and 90° build direction, respectively. SMAT is beneficial for SLM steel to reduce surface roughness (by ~ 87%) and eliminate internal porosity. The deformed layer of SLM steel shows a highly dense network of slip bands, distortion of grains, and hardness gradient (up to the depth of about 600 μm). Increase in surface hardness due to SMAT is maximum (~ 54%) for the sample having 90° build direction. Typical observation of deformation-induced martensite is absent for the SMAT-processed SLM steel. Under the higher load (especially, 20 N), the tribological response of sample manufactured in the 90° direction is superior amongst the non-treated samples. Severe surface deformation enhances the wear resistance and reduces the COF of SLM steel.

    ORCID iDs

    Kumar, Vikesh, Joshi, Manoj D., Pruncu, Catalin ORCID logoORCID: https://orcid.org/0000-0002-4926-2189, Singh, Indrasen and Hosmani, Santosh S.;