Test artifacts have been used to evaluate additive manufacturing (AM) systems since the early 1990s with over 65 artifacts published to date. Due to the system agnostic approach to artifact design, principally focused on geometric accuracy, there has yet to be a widely adopted artifact for laser powder bed fusion (LPBF). To speed qualification of LPBF, a rapid method that quantifies impacts of process

The present work focuses on the simulation of the heat treatment applied after printing of Ti-6Al-4V parts. The numerical tool aims at predicting the influence of heat treatment conditions (e.g. holding time, temperature) on the residual stress field and the distortions for SLM produced parts. The numerical model relies on a thermo-viscoplastic constitutive model. To determine the corresponding material

Additive manufacturing (AM) processes such as material extrusion and vat photopolymerization all require supports to print parts with overhang features. These additional supports using the same or different materials are a waste of materials since they need to be removed after the three-dimensional (3D) printing process and cannot be reused. The printing of supports is also time-consuming for the nozzle-based

Additive Manufacturing (AM) or 3D printing has enabled the production of increasingly complex parts that are difficult to produce with conventional manufacturing methods. Its additive nature has made it possible to create interlocking parts in a single production step. This creates opportunities for new ways of designing and producing mechanisms, which do not need to be assembled after production,

This study analyses literature data to identify optimised print parameters and assesses the consolidation, microstructure, and mechanical properties of Hastelloy-X printed by laser powder bed fusion. Effects of post annealing and hot-isostatic pressing (HIP) on the microstructure and mechanical properties are also revealed. The susceptibility to the solidification cracking was evaluated on the basis

Segregation defects, known as β-flecks, have long detracted from the widespread use of metastable β-Titanium alloys produced via solidification routes. These defects form when segregated β-stabilising solute such as chromium create localised phase instabilities which is detrimental to the alloy’s aging response and mechanical properties. This work explores whether Additive Manufacturing is a viable

Magnetic shape memory (MSM) alloys have a high potential as an emerging class of actuator materials for a new generation of fast and simple digital components. In this study, the MSM alloy Ni50.5Mn27.5Ga22.0 was built via laser powder bed fusion (L-PBF) using gas atomized powder doped with excess Mn to compensate for the expected evaporation of Mn during L-PBF. The built samples were subjected to stepwise

The microstructure characteristics and anodic electrochemical behavior of Hastelloy X fabricated by directed energy deposition were investigated in this work. The microstructure of as-deposited Hastelloy X mainly consisted of columnar dendrites along the deposition direction. The dendrite trunk was the γ matrix, and the inter-dendritic region was composed of the Mo-rich γ phase and carbides. After

Additively manufactured polymer heat exchangers are of recent interest in the thermal sciences due to their lightweight and intricate heat-transfer-enhancing geometrical features. The goal of the present research is to directly encapsulate phase-change material (PCM) into polymer filament for the purpose of 3D printing polymer heat exchangers capable of latent heat thermal energy storage and management

The materials library for Fused Filament Fabrication (FFF) additive manufacturing processes has been primarily dominated by amorphous thermoplastic materials. Semi-crystalline polymers form tough plastics due to their strong intermolecular forces, which makes them well suited for applications requiring wear and chemical resistance, thermal stability, and structural loading. However, they are infrequently

This work reports additive manufacturing of nickel-aluminum-bronze alloys by electron beam powder bed fusion (EB-PBF), with a relatively homogeneous microstructure at the micro- to meso-scale and exhibiting an exceptional combination of tensile strength and ductility — well surpassing that of conventionally wrought counterparts. The attainment of both high yield and ultimate tensile strength are attributed

A simulation model is presented in this work, capable to predict temperature and velocity of the extrudate as well as the compressive force acting on the filament in a fused filament fabrication (FFF) machine operating with a Bowden extruder. The simulation model is developed for future incorporation into a larger on-machine apparatus designed for process monitoring and adaptive control and destined

Additive manufacturing (AM) methods such as Aerosol Jet (AJ) printing allow the fabrication of structures via sintering of micro and/or nanoparticles, leading to microstructures that consist of various combinations of pore and grain sizes. It has been reported that AJ printed and sintered silver micropillars show an unusual behavior of high stiffness and high strain-to-failure for structures with high

Inkjet printing (IJP) has demonstrated its capabilities to produce high-quality and high-resolution parts, such as sensors, bio-chips, etc., with outstanding functionality. However, the quality of the printed parts can be endangered by the abnormal droplet jetting behaviors, which are substantially governed by the process dynamics and ambient conditions. Additionally, the droplet behaviors extensively

Single track scanning is a widely used method to evaluate the effects of rapid solidification of metals and to analyze their printability. Microstructure level stresses play a dominant role in causing material failure during deposition or poor performance on the finished product. This work formulates a thermomechanical crystal plasticity model capable of presenting microscale level evolution and residual

The aim of this work is to propose a methodology for rapidly predicting suitable process parameters for additive manufacturing of a 316L-Cu multi-material part with a compositional gradient by using machine learning. Specifically, an algorithm based on a multivariate Gaussian process is developed to predict part density and surface roughness for a given set of laser power, velocity, and hatch spacing

The design of porous structures of porous materials or porous media (PM) presents challenges that involve geometric modeling and manufacturing. Additive Manufacturing (AM) based on material extrusion is an important means for PM production. Although there are basic process parameters in this AM technology that allow for the creation of PM, its full potential has not been explored. Adding to that, the

A thin-wall sphere dome set is manufactured without supports being required using a direct energy deposition additive manufacturing process. A multi-axis tool path combined with a partitioning strategy is utilized. Two partitioning strategies and a rotary toolpath build strategy are applied. The partitioned samples have a 45 mm diameter, and the rotary toolpath sample has a 60 mm diameter. The wall

The usage of high laser power is one of the popular strategies to improve the productivity of selective laser melting technology. Herein, the single-track, single-layer and bulk 300M steel specimens were produced by high power selective laser melting (HP-SLM) to investigate the defects, densification mechanism, microstructure, tensile properties and impact toughnesses of HP-SLMed 300M steel parts.

The expanded design freedom offered by Additive Manufacture (AM) technologies is stimulating innovation in new directions, but it is also introducing new challenges in material characterisation. The inherent anisotropic behaviour observed in AM materials, like Ti-6Al-4V alloy, is of critical importance to safe and reliable implementation in structurally significant roles. To fully leverage the design

The advancement of drug delivery devices is critical for the individualization of patient treatment and the improvement of healthcare. Here, we introduce the 3DMNMEMS, a novel device that combines 3D printing, microneedles (MNs) and Microelectromechanical Systems (MEMS), allowing versatile and controllable by the user transdermal drug delivery. Hollow MNs were designed and 3D printed using Stereolithography

Three-dimensional concrete printing (3DCP) is an exciting new manufacturing paradigm for the construction industry. As this technology continues to grow and develop, it is revealing clear signs of progress towards industrial application with various global successes including the manufacturing of pedestrian bridges, houses, office buildings, emergency shelters and military structures. Much of the current

This work deals with the impact of prominent process parameters in laser powder bed fusion (L-PBF) technique, also called selective laser melting (SLM), on relevant properties of AlSi10Mg such as surface roughness and hardness. More particularly, the influence of scanning strategies, track energy density (TED), and of the offset between the contours and the bulk hatching were scrutinized. Basic thin

Laser-based powder bed fusion, due to its layer-by-layer nature, results in a unique stress profile in a part after the primary production process. The residual stresses are typically tensile near the top, while they are compressive near the bottom of the part. When it is removed without proper precautions, the part will bend excessively. In order to alleviate this deformation, a stress relief heat

Three-dimensional (3D) printing is a potential rapid prototyping process that may replace traditional manufacturing processes to fabricate lightweight cellular structures with superior energy absorption performance. In the present work, continuous fiber reinforced composite honeycomb structures (CFRCHSs) with excellent shape memory properties were manufactured through a fused filament fabrication (FFF)

Metal Big Area Additive Manufacturing (mBAAM) offers the potential to fabricate large scale tools at high deposition rates (15 lb/h+). 410 martensitic steel is a potential tooling material, owing to its low cost, good machinability and reasonable printability. During the mBAAM process, the shielding gas can have a significant impact on the material properties as well as the process cost. Therefore

Additive manufacturing allows the production of complex geometries with freedom for layers construction. Build orientation causes mechanical anisotropy and may affect the crystallographic structure enabling custom-tailored properties for the product. Despite the production advantages provided by the Powder Bed Fusion (PBF) process, some inherent defects, such as porosity and residual stress need monitoring

A novel crack-free Ti-modified Al-Cu-Mg alloy for SLM was developed here, based on the thermodynamic calculations of the crack susceptibility index and growth-restriction factor. We found that the introduction of Ti into the Al-Cu-Mg alloy effectively promoted the grain refinement and columnar-to-equiaxed grain transition as a result of the heterogeneous nucleation provided by Al3Ti precipitates. The

Amphiphobic surfaces are obtained by lowering the surface energy through changes in surface geometry. These changes can be designed on the surface, thereby altering its wettability, and in turn rendering it amphiphobic. The main geometrical entities behind this phenomenon are reentrant geometries which prevent the solid-liquid interface tension from breaking, thereby resulting in contact angles greater

This study describes for the first time the development of a silk powder-based 3D printing formulation that is compatible with Binder Jetting, a commercial additive manufacturing (AM) technique. The dynamic and bulk properties of the precursor powder were measured, including particle sizing, shape, flow energy, and compressibility, and the relationships between these properties, particle flow and printability

Fracture toughness, is a critical aspect of a component’s strength and structural integrity. In additive manufacturing (AM) of polymers and polymer composites, the fracture toughness of the manufactured part is influenced by the bonding between the layers which is dependent on the material, geometric and processing parameters. Known factors that influence the bond strength and interfacial adhesion

Damping mechanisms are a crucial factor for influencing the vibration behavior of dynamic systems. In many applications vibrations are undesirable and need to be reduced by appropriate measures. For instance, vibrations in vehicles can reduce driving comfort or in civil engineering resonance damage can occur in constructions. An interesting and cost-effective way of increasing damping is particle damping

Auxetic cellular structures offer improvements in some mechanical properties due to their negative Poisson’s ratio response when loaded. This study investigates and compares the effect of using multiple materials within three well researched cellular geometries, two auxetic: re-entrant and anti- tetrachiral, and one non-auxetic: hexagonal honeycomb. For each geometry, three different material configurations

Using multiple laser scanner units in Laser Powder Bed Fusion (LPBF) allows a significant increase in productivity compared to single scanner systems. However, the part quality can be affected by the interaction between simultaneous melting processes. This study focuses on part defects caused by the interference between an incident laser beam and the plume ejected from an adjacent melt pool generated

A near-infrared camera (NIR) is employed to monitor layer-by-layer in-situ electron beam powder bed fusion (E-PBF). We aim at demonstrating that such a device allows various kinds of flaws to be reliably captured thanks to qualitative thermal information. Defects such as distortions or uneven top surfaces can be detected in the NIR-images. Information about temperature heterogeneities can also be linked

Real-time monitoring of the additive manufacturing process offers the promise of guaranteeing product quality and increasing the efficiency of the printing process. This paper summarizes research results for the in situ monitoring of the printing process for the fused filament fabrication process. To have a systematic and comprehensive summary, different methods, devices, and achievements in a range

Projection micro stereolithography (PµSL) is an additive manufacturing tool that offers multiple advantages, including unparalleled resolution and throughput, but the ability to print high viscosity resin for large-scale parts is limited. One of the key challenges in PµSL is to separate a newly polymerized layer from the vat floor without damaging the part. Since the separation force scales with the

The effect of the residual oxygen concentration in the process atmosphere during laser-powder bed fusion (L-PBF) of Ti-6Al-4V was investigated, using an external oxygen monitoring system equipped with two types of oxygen sensors typically used in L-PBF hardware: a lambda probe and an electrochemical oxygen sensor. The recordings of the oxygen variations during L-PBF highlighted that the electrochemical

One of the barriers to the adoption of metal additively manufacturing by some industries is the absence of reliable part qualification procedures especially for components with complex geometries. Nondestructive evaluation (NDE) methods such as x-ray computed tomography (CT) and conventional ultrasonic testing (UT) have limitations in their abilities. X-ray CT is costly, hazardous, and offers limited

Material extrusion 3D printing has long been established for rapid prototyping and functional testing in many research and industry fields. However, its inconsistency and intrinsic defects (surface roughness and geometric inaccuracies) hinder its application in several areas, most notably “certify-as-you-build” small-batch prototyping and large-batch production. In this study, we present an approach