scholarly journals CAPTURING OF UNEVEN DEFORMATIONS OF LIGHTENED 3D PRINTED PARTS

2020 ◽  
Vol 15 (2) ◽  
Author(s):  
Filip Klejch ◽  
Eva Schmidová ◽  
Jakub Vágner ◽  
Ivana Zetková
Keyword(s):  
Automotive Application ◽  
Total Deformation ◽  
Deformation Response ◽  
Final Fracture ◽  
State Of Stress ◽  
Internal Structures ◽  
3D Printed ◽  
Test Record ◽  
Stress And Deformation ◽  
Cylindrical Samples

This paper deals with the problematics of tensile testing of maraging steel lightweight cylindrical samples with internal structures, intended for automotive application. The samples were made with DMLS technology and tensile tested under the static strain rate of 0.002 s-1. During the loading, uneven deformations and multiple necking occurred on the samples. The mentioned effect significantly affects the state of stress and deformation at the final fracture zone, as well as the total deformation into the fracture, which means that it actually distorts the standard tensile test record. Therefore, a methodology for capturing the deformation response using the ARAMIS optical system was proposed. The methodology is presented and verified by a set of experiments for BCC internal structure.

scholarly journals INFLUENCE OF PRINTING AND LOADING DIRECTION ON MECHANICAL RESPONSE IN 3D PRINTED MODELS OF HUMAN TRABECULAR BONE

2018 ◽  
Vol 18 ◽  
pp. 24 ◽  
Author(s):  
Tomáš Doktor ◽  
Ivana Kumpová ◽  
Sebastian Wroński ◽  
Maciej Śniechowski ◽  
Jacek Tarasiuk ◽  
...  
Keyword(s):  
Trabecular Bone ◽  
Mechanical Response ◽  
Plastic Region ◽  
Human Donor ◽  
Deformation Response ◽  
Human Trabecular Bone ◽  
Loading Mode ◽  
Loading Direction ◽  
3D Printed ◽  
X Ray Computed

The paper deals with investigation on directional variations of mechanical response in 3D printed models of human trabecular bone. Sample of trabecular bone tissue was resected from human donor and 3D model was obtained by X-ray computed tomography. Then a series of cubical samples was prepared by additive manufacturing technique and tested by uniaxial compression loading mode. Mechanical response was compared in nine different combinations of direction of 3D printing and loading direction. The results show neglectible influence on the deformation response in elastic region (stiffness) and significant changes of the behaviour in plastic region (stress and strain at yield point, strain at full collapse).

scholarly journals 3D-printed biological cell phantom for testing 3D quantitative phase imaging systems

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Michał Ziemczonok ◽  
Arkadiusz Kuś ◽  
Piotr Wasylczyk ◽  
Małgorzata Kujawińska
Keyword(s):  
Mammalian Cells ◽  
Phase Imaging ◽  
Biological Cell ◽  
Quantitative Phase Imaging ◽  
Quantitative Phase ◽  
Two Photon ◽  
Internal Structures ◽  
Life Scale ◽  
3D Printed ◽  
Further Development

AbstractAs the 3D quantitative phase imaging (QPI) methods mature, their further development calls for reliable tools and methods to characterize and compare their metrological parameters. We use refractive index engineering during two-photon laser photolithography to fabricate a life-scale phantom of a biological cell with internal structures that mimic optical and structural properties of mammalian cells. After verification with a number of reference techniques, the phantom is used to characterize the performance of a limited-angle holographic tomography microscope.

scholarly journals Simulation of the impact resistance of Kilo type submarine loaded with non-contact mine explosion

2017 ◽  
pp. 99-110
Author(s):  
Bogdan Szturomski ◽  
Radosław Kiciński
Keyword(s):  
Finite Element Method ◽  
Pressure Wave ◽  
Impact Resistance ◽  
Acoustic Medium ◽  
The Finite Element Method ◽  
State Of Stress ◽  
Stress And Deformation ◽  
Submarine Hull ◽  
Explosion Load ◽  
The Impact

The paper presents simulations of the state of stress and deformation of the Kilo class submarine hull loaded from pressure wave of non-contact mine explosion. To accomplish the task the finite element method was used. Pressure wave was described by T. L. Geers’a and K. S. Hunter model. The way of modeling the pressure wave using the acoustic medium implemented to CAE programs was shown. To describe the material an elastic-plastic model of Jonson-Cook which takes into account the speed of deformation was used. The paper presents pressure distribution on the Kilo type submarine hull exposed on 100 kg of TNT explosion load in front of the bow of the ship.

3D Printing of True Pore-Scale Berea Sandstone and Digital Rock Verification

SPE Journal ◽  
2021 ◽  
pp. 1-6
Author(s):  
Aobo Li ◽  
Shuo Zhang ◽  
Chicheng Xu ◽  
Xiaoguang Zhao ◽  
Xin Zhang
Keyword(s):  
3D Printing ◽  
Rock Physics ◽  
Pore Scale ◽  
Berea Sandstone ◽  
Digital Rock Physics ◽  
Digital Rock ◽  
Natural Rock ◽  
Internal Structures ◽  
Geometric Scaling ◽  
3D Printed

Summary In this study, we used two-photon polymerization 3D printing technology to successfully print the first true pore-scale rock proxy of Berea sandstone with a submicrometer resolution. Scanning electron microscope (SEM) and computed tomography (CT) images of the 3D-printed sample were compared with the digital file used for printing to verify the rock’s internal structures. Petrophysical properties were estimated with a digital rock physics (DRP) model based on the 3D-printed sample's initial pore network. The results show that our 3D-printing workflow was able to reproduce true-scale 3D porous media such as Berea sandstone with a submicrometer resolution. With a variety of materials and geometric scaling options, 3D printing of nearly identical rock proxies provides a method to conduct repeatable laboratory experiments without destroying natural rock samples. Rock proxy experiments can potentially validate numerical simulations and complement existing laboratory measurements.

A Micromechanical Bending Stage for Studying Mechanical Properties of Materials Using Nanoindenter

2015 ◽  
Vol 82 (12) ◽  
Author(s):  
Mohamed Elhebeary ◽  
M. Taher A. Saif
Keyword(s):  
Analytical Model ◽  
Small Volume ◽  
Bending Test ◽  
Bending Stress ◽  
Entire Volume ◽  
Premature Failure ◽  
State Of Stress ◽  
3D Printed ◽  
Properties Of Materials ◽  
Good Agreement

An analytical and computational model of a novel bending stage is presented. The stage applies bending moments on micro/nanoscale beam specimens using a nanoindenter. In uniaxial tests, any flaw within the entire volume of the specimen may lead to fracture before material yields. The new stage minimizes the volume of material under a uniaxial state of stress in the specimen, but maximizes bending stress over a small volume such that high stresses can be reached within a small volume on the specimen without a premature failure by fracture. The analytical model of the stage accounts for the geometric nonlinearity of the sample, but assumes simplified boundary conditions. It predicts the deflection and stresses in the specimen beam upon loading. The numerical model of the stage and the specimen employing a finite element (FE) package tests the validity of the analytical model. Good agreement between analytical and numerical results shows that the assumptions in the analytical model are reasonable. Therefore, the analytical model can be used to optimize the design of the stage and the specimen. A design of the stage is presented that results in axial/bending stress < 2% in the sample. In order to test the feasibility of the proposed design, a 3D printed stage and a sample are fabricated using the Polyamide PA2200. Bending test is then carried out employing an indenter. Elastic modulus of PA2200 is extracted from the load-deflection data. The value matches closely with that reported in the literature.

3D Printed Ceramics for Tableware, Artists/Designers and Specialist Applications

2014 ◽  
Vol 608 ◽  
pp. 351-357 ◽  
Author(s):  
David Huson ◽  
Stephen Hoskins
Keyword(s):  
Ceramic Body ◽  
Ceramic Materials ◽  
The West ◽  
Novel Technique ◽  
Internal Structures ◽  
Short Run ◽  
3D Printers ◽  
3D Printed ◽  
The University ◽  
Forming Methods

The Centre for Fine Print Research at the University of the West of England has over five years experience in the 3D printing of ceramic materials. The first project undertaken was to investigate the use of 3D technologies for artists and resulted in the development of a patented ceramic body suitable for use in Z Corporation 3D printers. After bisque firing this material can be further processed using conventional glazing and decorating techniques. A follow on project has resulted in a modified ceramic body and the development of firing supports to enable thin section ceramic tableware to be produced for ceramic industry concept modelling and short run or one-off pieces for artists and designers. This paper will detail the progress of the research and will explain by using case studies and examples of collaboration with a leading UK pottery manufacturer, individual artists and designers how this novel technique can be utilised to form shapes and forms difficult or impossible to realise by conventional forming methods. The potential of how the ability to form ceramic objects with complex internal structures could be beneficial to more specialist ceramics industries will also be explored.

Sign in / Sign up

Export Citation Format

Share Document