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Materials Science in Additive Manufacturing Measuring the porosity of AM components

overview of the individual process categories and their as fused deposition modeling (FDM) and can also produce
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technological advantages and disadvantages. metallic components, for example from 316l stainless steel,
AM technologies utilize different principles to process in a two-stage production process consisting of the actual
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a wide range of materials. In this study, four AM processes printing and a subsequent debinding and sintering step. In
with different printing materials are analyzed as examples, powder bed fusion (PBF), an energy source is used to locally
which are characteristic for the broad spectrum of AM sinter or fuse a powdered material. In the second process
processes and materials with regard to the results of the 3D studied, selective laser sintering (SLS), a laser is used to sinter
printing process. In the first process examined, the material polyamide 12 (PA12) powder whereas in the third examined
extrusion (MEX) process, a thermoplastic filament is applied process, electron beam melting (EBM), an electron beam is
layer by layer to a build platform by softening and localized used to produce metallic components by completely melting
application via a heated nozzle. The process is also known titanium powder. VAT photo-polymerization (VPP) is a

Table 1. Additive manufacturing process categories according to published literature 1,2

Process category Definition Advantages Disadvantages
Binder jetting AM process in which a liquid Wide range of materials, low Multi-stage process, extensive
binder is selectively applied to powder consumption, high post-processing, high porosity, low
powder materials to cause them productivity, no support strength
to bond structures, high speed

Directed energy AM process that uses focused Production of large parts, fast Low resolution and poor surface
deposition thermal energy to fuse materials repair of metal parts, high quality, no support structures, limited
together during deposition process speed, low waste design freedom

Material extrusion AM process in which materials Simple and familiar process, Low resolution and production
are selectively applied through a wide range of materials, accuracy, poor surface quality, a lot
nozzle or orifice cost-effective, mechanically of post-processes, slow production
resilient components process

Material jetting AM process in which drops of High-precision process, good Low process speed, increased
the starting material are applied material combination, low post-processing effort, poor
in a targeted manner material loss, high density and mechanical resilience, expensive
strength

Powder bed fusion AM process in which thermal High density and strength, Relatively slow and expensive, limited
energy selectively melts areas of high precision, great design material variety, high process costs,
a powder bed freedom, good mechanical poor powder recycling, limited
properties and load-bearing surface quality
capacity

Sheet lamination AM process in which sheets of Fast process, suitable for Niche process, a lot of post-processes,
material are joined to form a large components, simple little material variety, strong
component technology anisotropy of the components, high
level of wastage

VAT AM process in which liquid Very high accuracy, smooth Necessity of support structures, brittle
photo-polymerization photopolymer is selectively surfaces, low material components, ultraviolet post-curing
cured in a bath by light-activated consumption if necessary
polymerization

Abbreviation: AM: Additive manufacturing.
Volume 4 Issue 2 (2025) 2 doi: 10.36922/MSAM025090010