TY - JOUR
T1 - Classifying shape of internal pores within AlSi10Mg alloy manufactured by laser powder bed fusion using 3D X-ray micro computed tomography
T2 - influence of processing parameters and heat treatment
AU - Hastie, James C
AU - Kartal, Mehmet
AU - Carter, Luke N
AU - Attallah, Moataz M
AU - Mulvihill, Daniel M
N1 - The authors gratefully acknowledge the support provided by the EPSRC (grant EP/R021694/1). The authors also wish to thank Rosie Bird at the University of Aberdeen for assisting with Avizo.
PY - 2020/5/1
Y1 - 2020/5/1
N2 - Internal porosity of metallic parts manufactured by laser powder bed fusion (LPBF) is governed by processing parameters including laser power, scanning speed, scan spacing and layer thickness. To fully understand the influence of processing parameters it is important to categorise the shape of process defects (pores) in 3D beyond the degree of sphericity alone. In the present paper, AlSi10Mg samples were manufactured using 30 unique LPBF parameter combinations and analysed using high resolution X-ray micro computed tomography (XμCT). The shapes of individual pores are classified and studied using an approach based on the similarity of 3D pore descriptors with simplified artificial objects. Porosity within high as-fabricated densification builds can be reduced to virtually negligible by hot isostatic pressing (HIPping), which was found to fully or partially close (flatten) pores. Subsequent T6 treatment causes pores to reopen and resemble their original shape. The effects of treatment are sensitive to pore size.
AB - Internal porosity of metallic parts manufactured by laser powder bed fusion (LPBF) is governed by processing parameters including laser power, scanning speed, scan spacing and layer thickness. To fully understand the influence of processing parameters it is important to categorise the shape of process defects (pores) in 3D beyond the degree of sphericity alone. In the present paper, AlSi10Mg samples were manufactured using 30 unique LPBF parameter combinations and analysed using high resolution X-ray micro computed tomography (XμCT). The shapes of individual pores are classified and studied using an approach based on the similarity of 3D pore descriptors with simplified artificial objects. Porosity within high as-fabricated densification builds can be reduced to virtually negligible by hot isostatic pressing (HIPping), which was found to fully or partially close (flatten) pores. Subsequent T6 treatment causes pores to reopen and resemble their original shape. The effects of treatment are sensitive to pore size.
KW - laser powder bed fusion
KW - selective laser melting
KW - X-ray micro computed tomography
KW - porosity classification
KW - hot isostatic pressing
KW - T6 heat treatment
KW - POROSITY
KW - Laser powder bed fusion
KW - QUANTIFICATION
KW - Hot isostatic pressing
KW - Porosity classification
KW - MECHANICAL-PROPERTIES
KW - Selective laser melting
KW - MELTED ALSI10MG
KW - MICROSTRUCTURE
UR - http://www.scopus.com/inward/record.url?scp=85080975585&partnerID=8YFLogxK
U2 - 10.1016/j.matchar.2020.110225
DO - 10.1016/j.matchar.2020.110225
M3 - Article
VL - 163
JO - Materials Characterization
JF - Materials Characterization
SN - 1044-5803
M1 - 110225
ER -
