scholarly journals Morphology and surface topography of Ti6Al4V lattice structure fabricated by selective laser sintering

2017 ◽  
Vol 65 (1) ◽  
pp. 85-92 ◽  
Author(s):  
J. Maszybrocka ◽  
A. Stwora ◽  
B. Gapiński ◽  
G. Skrabalak ◽  
M. Karolus
Keyword(s):  
Porous Structure ◽  
Surface Topography ◽  
Lattice Structure ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Interdisciplinary Approach ◽  
Porous Metal ◽  
Laser Sintering ◽  
Qualitative Assessment ◽  
Three Dimensional Model

Abstract Construction of metallic implants with a porous structure that mimics the biomechanical properties of bone is one of the challenges of orthopedic regenerative medicine. The selective laser sintering technique (SLS) allows the production of complex geometries based on three-dimensional model, which offers the prospect of preparing porous metal implants, in which stiffness and porosity can be precisely adjusted to the individual needs of the patient. This requires an interdisciplinary approach to design, manufacturing and testing of porous structures manufactured by selective sintering. An important link in this process is the ability to assess the surface topography of the struts of porous structure. The paper presents a qualitative assessment of the surface morphology based on SEM studies and methodology that allows for quantitative assessment of stereometric structure based on micro-tomographic measurements.

Fabrication of three dimensional open porous regular structure of PA-2200 for enhanced strength of scaffold using selective laser sintering

2016 ◽  
Vol 22 (4) ◽  
pp. 752-765 ◽  
Author(s):  
Jatender Pal Singh ◽  
Pulak M. Pandey ◽  
Anita Kamra Verma
Keyword(s):  
Porous Structure ◽  
Pore Size ◽  
Process Parameters ◽  
Cell Structure ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Laser Sintering ◽  
Open Cell ◽  
Content Type ◽  
Open Porous Structure

Purpose Scaffolds are essentially required to have open porous structure for facilitating bone to grow. They are generally placed on those bone defective/fractured sites which are more prone to compressive loading. Open porous structure lacks in strength in comparison to solid. Selective laser sintering (SLS) process is prominently used for fabrication of polymer/composite scaffolds. So, this paper aims to study for fabrication of three-dimensional open porous scaffolds with enhanced strength, process parameters of SLS of a biocompatible material are required to be optimized. Design/methodology/approach Regular open porous structures with suitable pore size as per computer-aided design models were fabricated using SLS. Polyamide (PA-2200) was used to fabricate the specimen/scaffold. To optimize the strength of the designed structure, response surface methodology was used to design the experiments. Specimens as per ASTM D695 were fabricated using SLS and compressive testing was carried out. Analysis of variance was done for estimating contribution of individual process parameters. Optimized process parameters were obtained using a trust region algorithm and correlated with experimental results. Accuracy of the fabricated specimen/scaffold was also assessed in terms of IT grades. In vitro cell culture on the fabricated structures confirmed the biocompatibility of polyamide (PA-2200). Findings Optimized process parameters for open cell process structures were obtained and confirmed experimentally. Laser power, hatch spacing and layer thickness have contributed more in the porous part’s strength than scan speed. The accuracy of the order of IT16 has been found for all functional dimensions. Cell growth and proliferation confirmed biocompatibility of polyamide (PA-2200) for scaffold applications. Originality/value This paper demonstrates the biocompatibility of PA-2200 for scaffold applications. The optimized process parameters of SLS process for open cell structure having pore size 1.2 × 1.2 mm2 with strut diameter of 1 mm have been obtained. The accuracy of the order of IT16 was obtained at the optimized process factors.

Calcium sulfate bone scaffolds with controllable porous structure by selective laser sintering

2015 ◽  
Vol 22 (5) ◽  
pp. 1171-1178 ◽  
Author(s):  
Jianhua Zhou ◽  
Chengde Gao ◽  
Pei Feng ◽  
Tao Xiao ◽  
Cijun Shuai ◽  
...  
Keyword(s):  
Porous Structure ◽  
Calcium Sulfate ◽  
Selective Laser Sintering ◽  
Laser Sintering ◽  
Bone Scaffolds

scholarly journals Advanced Trans-Tibial Socket Fabrication Using Selective Laser Sintering

2007 ◽  
Vol 31 (1) ◽  
pp. 88-100 ◽  
Author(s):  
Bill Rogers ◽  
Gordon W. Bosker ◽  
Richard H. Crawford ◽  
Mario C. Faustini ◽  
Richard R. Neptune ◽  
...  
Keyword(s):  
Solid Freeform Fabrication ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Structural Features ◽  
Laser Sintering ◽  
Health Science ◽  
Science Center ◽  
University Of Texas ◽  
Three Dimensional Objects ◽  
Prosthetic Socket

There have been a variety of efforts demonstrating the use of solid freeform fabrication (SFF) for prosthetic socket fabrication though there has been little effort in leveraging the strengths of the technology. SFF encompasses a class of technologies that can create three dimensional objects directly from a geometric database without specific tooling or human intervention. A real strength of SFF is that cost of fabrication is related to the volume of the part, not the part's complexity. For prosthetic socket fabrication this means that a sophisticated socket can be fabricated at essentially the same cost as a simple socket. Adding new features to a socket design becomes a function of software. The work at The University of Texas Health Science Center at San Antonio (UTHSCSA) and University of Texas at Austin (UTA) has concentrated on developing advanced sockets that incorporate structural features to increase comfort as well as built in fixtures to accommodate industry standard hardware. Selective laser sintering (SLS) was chosen as the SFF technology to use for socket fabrication as it was capable of fabricating sockets using materials appropriate for prosthetics. This paper details the development of SLS prosthetic socket fabrication techniques at UTHSCSA/UTA over a six-year period.

Control-Oriented Modeling and Repetitive Control in In-Layer and Cross-Layer Thermal Interactions in Selective Laser Sintering

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Dan Wang ◽  
Tianyu Jiang ◽  
Xu Chen
Keyword(s):  
High Performance ◽  
Selective Laser Sintering ◽  
Repetitive Control ◽  
Three Dimensional ◽  
Process Variations ◽  
Laser Sintering ◽  
Laser Source ◽  
Cross Layer ◽  
Modeling And Control ◽  
Melt Pool

Abstract Although laser-based additive manufacturing (AM) has enabled unprecedented fabrication of complex parts directly from digital models, broader adoption of the technology remains challenged by insufficient reliability and in-process variations. In pursuit of assuring quality in the selective laser sintering (SLS) AM, this paper builds a modeling and control framework of the key thermodynamic interactions between the laser source and the materials to be processed. First, we develop a three-dimensional finite element simulation to understand the important features of the melt pool evolution for designing sensing and feedback algorithms. We explore how the temperature field is affected by hatch spacing and thermal properties that are temperature-dependent. Based on high-performance computer simulation and experimentation, we then validate the existence and effect of periodic disturbances induced by the repetitive in- and cross-layer thermomechanical interactions. From there, we identify the system model from the laser power to the melt pool width and build a repetitive control algorithm to greatly attenuate variations of the melt pool geometry.

Numerical Simulation of Direct Metal Laser Sintering of Single-Component Powder on Top of Sintered Layers

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Bin Xiao ◽  
Yuwen Zhang
Keyword(s):  
Laser Scanning ◽  
Three Dimensional ◽  
Processing Parameters ◽  
Laser Sintering ◽  
Liquid Pool ◽  
Sintering Process ◽  
Direct Metal Laser Sintering ◽  
Three Dimensional Model ◽  
Gaussian Laser Beam ◽  
Scanning Velocity

A three-dimensional model describing melting and resolidification of direct metal laser sintering of loose powders on top of sintered layers with a moving Gaussian laser beam is developed. Natural convection in the liquid pool driven by buoyancy and Marangoni effects is taken into account. A temperature transforming model is employed to model melting and resolidification in the laser sintering process. The continuity, momentum, and energy equations are solved using a finite volume method. The effects of dominant processing parameters including number of the existing sintered layers underneath, laser scanning velocity, and initial porosity on the sintering process are investigated.

Dimensional error of selective laser sintering, three-dimensional printing and PolyJet™ models in the reproduction of mandibular anatomy

2009 ◽  
Vol 37 (3) ◽  
pp. 167-173 ◽  
Author(s):  
Danilo Ibrahim ◽  
Tiago Leonardo Broilo ◽  
Claiton Heitz ◽  
Marília Gerhardt de Oliveira ◽  
Helena Willhelm de Oliveira ◽  
...  
Keyword(s):  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Laser Sintering ◽  
Dimensional Error ◽  
Three Dimensional Printing ◽  
Dimensional Printing

Three-Dimensional Modeling of Selective Laser Sintering of Two-Component Metal Powder Layers

2005 ◽  
Vol 128 (1) ◽  
pp. 299-306 ◽  
Author(s):  
Tiebing Chen ◽  
Yuwen Zhang
Keyword(s):  
Metal Powder ◽  
Continuous Wave ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Laser Sintering ◽  
Powder Layer ◽  
Metal Powders ◽  
Gaussian Laser Beam ◽  
Scanning Velocity ◽  
Three Dimensional Modeling

Laser sintering of a metal powder mixture that contains two kinds of metal powders with significantly different melting points under a moving Gaussian laser beam is investigated numerically. The continuous-wave laser-induced melting accompanied by shrinkage and resolidification of the metal powder layer are modeled using a temperature-transforming model. The liquid flow of the melted low-melting-point metal driven by capillary and gravity forces is also included in the physical model. The numerical results are validated by experimental results, and a detailed parametric study is performed. The effects of the moving heat source intensity, the scanning velocity, and the thickness of the powder layer on the sintering depth, the configuration of the heat affected zone, and the temperature distribution are discussed.

Simultaneous, laser-sintered, three-dimensional modelling of bony structures and soft tissue for surgical navigation of extended cholesteatoma

2009 ◽  
Vol 124 (5) ◽  
pp. 564-568 ◽  
Author(s):  
M Suzuki ◽  
Y Ogawa ◽  
T Hasegawa ◽  
S Kawaguchi ◽  
K Yukawa ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Soft Tissue ◽  
Soft Tissues ◽  
Surgical Navigation ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Styloid Process ◽  
Dimensional Structure ◽  
Dimensional Model ◽  
Three Dimensional Model

AbstractAim:To examine the usefulness of a three-dimensional model for surgical navigation of cholesteatoma.Materials and method:A three-dimensional model was prototyped using selective laser sintering. Based on detailed computed tomography data, powder layers were laser-fused and accumulated to create a three-dimensional structure. The computed tomography threshold was adjusted to simultaneously replicate bony structures and soft tissues.Results:The cholesteatoma, major vessels and bony structures were well replicated. This laser-sintered model was used to aid surgery for recurrent cholesteatoma. The cholesteatoma, which extended from the hypotympanum through the styloid process sheath and the internal carotid artery sheath, was removed safely via a minimal skin incision.Conclusion:The laser-sintered model was useful for surgical planning and navigation in a cholesteatoma case involving complex bony structures and soft tissue.

Sign in / Sign up

Export Citation Format

Share Document