Fatigue life assessment of metal additive manufacturing (AM) products has remained challenging due to the uncertainty as–built defects, heterogeneity microstructure, and residual stress. In past few years, many works have been conducted develop models in order predict fatigue AM samples by considering existence inherent defects. This review paper addresses main issues regarding parts effect defects post processing strategies. Mechanisms that are contributing failure categorized discussed...

The effect of using multiple materials within hexagonal and re-entrant (auxetic) cellular structures was investigated. For each topology, three different material configurations including (a) Nylon, (b) Carbon fibre reinforced Nylon (c) Glass were used. A numerical model constituted to imitate the compressive behaviour these multi-material under quasi-static loading. validation, samples printed with Fused Filament Fabrication (FFF) technique experimentally tested. good correlation captured...

In the present study, a comparative compression investigation of anti-tetrachiral and modified re-entrant lattices was conducted in-plane direction using experimental numerical analyses. Lattice structures were manufactured fused deposition modelling 3D printing technology crushed at quasi-static condition. Nonlinear finite element (FE) models both established, FE results systematically compared with results. The onset densification phases determined numerically. Results indicate that...

Different additive manufacturing modalities enable the production of multi-material components which can be used in a wide range industrial applications. The prediction mechanical properties these via finite element modelling rather than through testing is critical terms cost and time. However, due to higher computational time spent on lattice structures, different methods have been investigated accurately predict properties. For this purpose, study proposes use homogenization method two...

This study aimed to determine the effects of design parameters, including liquid/solid ratio (L/S), Na2SiO3/NaOH weight ratio, and curing temperature, on class F fly ash-based geopolymer composites. For this purpose, two disparate sources ash were supplied from Çatalağzı (FA) İsken Sugözü (FB) Thermal Power Plants in Turkey. Two different L/S ratios 0.2 0.4 used. The alkaline solutions 1, 1.5, 2, 2.5, 3 by for each type mixture. Then, 40 mixes cured at specific temperatures (70 °C 100 °C) 24...

Crash box structures are used for mitigating the transfer of impact sourced loads to vehicle cabinet prevent injuries and casualties. They designed in shape tubes, during loading, they can be depleted as sacrificial structures. For increasing energy absorption capability, particular types fillers crash boxes. In present study, outcome two filling on capability boxes is investigated experimentally numerically. As materials, PolyJet printed polymer re-entrant anti-tetrachiral utilized...

Triply periodic minimal surface (TPMS) structures offer lightweight and high-stiffness solutions to different industrial applications. However, testing of these calculate their mechanical properties is expensive. Therefore, it important predict the effectively. This study focuses on effectiveness using regression analysis equations based experimental results diamond, gyroid, primitive TPMS with volume fractions build orientations. Gyroid, specimens three (0.2, 0.3, 0.4) were manufactured a...

Abstract Triply periodic minimal surface (TPMS) lattices have drawn great attention both in academic and industrial perspective due to their outstanding mechanical behaviours. Additive manufacturing (AM) modalities enable the production of these very easily. However, dimensional inaccuracy is still one problems that AM faces with. Manufacturing with modalities, then measuring critical dimensions making design changes accordingly a costly process. Therefore, it necessary predict deviation...

In this study, the cyclic compression and crush behavior of chiral auxetic lattice structures produced from titanium alloy (Ti6Al4V) metallic powder using electron beam melting (EBM) additive manufacturing technology is investigated numerically experimentally. For material characterization understanding EBM printed parts, tensile three-point flexural tests were conducted. Log signals during process to confirm stability health parts. Furthermore, a compressive load profile was applied units...

Our research investigated the energy absorption characteristics of chiral auxetic lattices filled cylindrical composite tubes subjected to a uniaxial and lateral quasi-static load. The lattice structures were manufactured using 3D printing technique. Carbon fiber without filler material initially crushing same types experiment then performed on tubes. For different cases, load–displacements curves analyzed specific (SEA) values compared. SEA capability for axial decreased in comparison with...

Lattice structures are promising materials in the terms of energy absorption, acoustic and vibrational damping, high strength-to-weight ratios thermal management capabilities. In particular, auxetic lattice structures, among others, show absorption performances due to their characteristic negative Poisson's ratio. this study, it is aimed compare deformation mechanisms under quasi-static crush loads. Ti6Al4V tensile test specimens were produced with Electron Beam Melting (EBM) Additive...

The present study focuses on producibility and surface roughness characteristics of airfoil geometries their effect aerodynamic performance for different velocities, values angles attack. Two tray orientations (along X Y axis), two build directions (vertical horizontal) finish settings (matte glossy) were used to evaluate the these parameters both up- down-facing surfaces airfoils produced by PolyJet. On surfaces, measurements performed crossing directions. results showed that horizontal...

This paper presents a modal analysis of honeycomb and re-entrant lattice structures to understand the change in natural frequencies when multi-material configuration is implemented. For this purpose, parallel nylon ligaments within are replaced with chopped continuous carbon fibre constitute configurations. each set, first five were compared using detailed finite element models. configuration, three different boundary conditions considered, which free–free clamping at two sides that...

Abstract In additive manufacturing (AM) technologies, support structures are used to anchor a part the base plate and prevent from distortions dimensional deviations due high thermal gradients during manufacturing. Because do not contribute any value need be removed after with extra costs time, different studies have focused on minimizing use of such structures. However, it is almost impossible totally eliminate for structures, especially in very complex parts overhang surfaces. Therefore,...

Yüksek ısı transfer kabiliyeti, enerji absorbe edebilme ve ses izolasyonu özelliklerinden dolayı kafes yapılar havacılık, otomotiv biyomedikal sanayii başta olmak üzere bir çok alanda kullanılmaktadır. Kafes yapıların bu kabiliyetleri üzerinde farklı proses geometrik parametreler etkili olmaktadır. Farklı endüstriyel uygulamalarda, ilgili yapısının uygun ile birlikte kullanılmasının, uygulama sonucu elde edilen verimi arttıracağı bilinen gerçektir. Bu çalışma, Taguchi deney tasarımı...

The purpose of this study is to examine the energy absorption characteristics two different auxetic honeycombs that have negative Poisson's ratio (NPR) subjected an axial quasi-static load. total mass and volume are kept nearly equal. As load-extension graphs examined, it observed a smooth transition peak forces during crush for second one which has more strut. On other hand, first better capability.

Impact phenomenon is significant for our lives. It can be encountered in many fields. The critical areas are debris impact space, bird striking on aircraft, ballistic and traffic accidents. For preventing the effect of impacts, some engineering structures improved used recently. These to absorb energy by avoiding transfer high magnitude load which risks human life essential part vehicles that stems from impact. road vehicles, crush tubes this purpose. However, they not efficient, so tube...

The effect of using multiple materials within hexagonal and re-entrant (auxetic) cellular structures was investigated. For each topology, three different material configurations including (a) Nylon, (b) Carbon fibre reinforced Nylon (c) Glass were used. A numerical model constituted to imitate the compressive behaviour these multi-material under quasi-static loading. validation, samples printed with Fused Filament Fabrication (FFF) technique experimentally tested. good correlation captured...

Thermal nature of laser powder bed fusion process (LPBF) causes residual stress formation on the part during printing which may cause penetration some layers towards inside or outside nominal geometry called shrink line. Shrink line affects dimensional accuracy and fatigue life produced parts. The prediction via numerical methods is important to mitigate high cost trial-and-error printing. This study focused in triply periodic minimum surface (TPMS) lattices by LPBF process. effect TPMS...

Multi morphology lattices are composite lattice structures formed by different types of in configurations based on engineering application needs. These can be manufactured with additive manufacturing modalities, specifically laser powder bed fusion process. However, due to the high cost and time spent these components, it is necessary predict properties parts before build numerical methods. This study focused prediction dimensional deviation produced multi composed Schoen Gyroid, Schwarz...