23 research outputs found
HIGH PERFORMANCE COMPUTING AND PROCESS CONTROL OF ADDITIVE LAYER MANUFACTURING METHODS FOR POLYMER PRODUCT METAL TOOLS PRODUCTION
Purpose of the study: Additive layer manufacturing is basically different from the traditional formative manufacturing process where a complete structure can be constructed into designed shape from layer to layer manufacturing rather than other methods or casting, forming or other machining processes. Additive layer manufacturing is a highly versatile, flexible, and customizable.
Methodology: In this paper, we discussed high-performance computing and process control of AM methods by using different parameters. The significant interest in making complex, innovative and robust products by using AM methods to great extent to deal with work is needed in AM challenges relevant to key enabling technologies namely different materials and metrology to achieve functionally and reproductive ways.
Main Findings: In this paper, we discussed major processes that highly accurate and the key applications, challenges and recent developments of future additive Am processes.
Applications of this study: Additive layer manufacturing methods to develop the most highly and controlled methods for producing a variety of complex shapes and structures. The significant role of AM layer technology is to make produce the most economical and highly effective methods. In this study, we compared different AM methods for achieving the most highly and controlled methods of AM technology.
Novelty/Originality of this study: Today manufacturing trends are very highly impacted by technologies globalizations. Various manufactures are using layer manufacturing into their best practices so that they can be changes in the global economy and manufacturing
Studying trabecular bone samples demonstrates a power law relation between deteriorated structure and mechanical properties - a study combining 3D printing with the finite element method
IntroductionThe bone volume fraction (BV/TV) significantly contributes to the mechanical properties of trabecular bone. However, when studies compare normal trabeculae against osteoporotic trabeculae (in terms of BV/TV decrease), only an “average” mechanical result has been determined because of the limitation that no two trabecular structures are the same and that each unique trabecular structure can be mechanically tested only once. The mathematic relation between individual structural deterioration and mechanical properties during aging or the osteoporosis process has yet to be further clarified. Three-dimensional (3D) printing and micro-CT-based finite element method (μFEM) can assist in overcoming this issue.MethodsIn this study, we 3D printed structural-identical but BV/TV value-attenuated trabecular bones (scaled up ×20) from the distal femur of healthy and ovariectomized rats and performed compression mechanical tests. Corresponding μFEM models were also established for simulations. The tissue modulus and strength of 3D printed trabecular bones as well as the effective tissue modulus (denoted as Ez) derived from μFEM models were finally corrected by the side-artifact correction factor.ResultsThe results showed that the tissue modulus corrected, strength corrected and Ez corrected exhibited a significant power law function of BV/TV in structural-identical but BV/TV value-attenuated trabecular samples. DiscussionUsing 3D printed bones, this study confirms the long-known relationship measured in trabecular tissue with varying volume fractions. In the future, 3D printing may help us attain better bone strength evaluations and even personal fracture risk assessments for patients who suffer from osteoporosis
NASA Tech Briefs, July/August 1987
Topics include: NASA TU Services; New Product Ideas; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Fabrication Technology; Machinery; Mathematics and Information Sciences; Life Sciences
NASA Tech Briefs, July 1999
Topics: Test and Measurement; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Software; Mechanics; Machinery/Automation; Bio-Medical; Books and Reports; Semiconductors/ICs
Non-destructive testing of the parts manufactured by Direct Metal Laser Sintering
Published ThesisInterest in Additive Manufacturing (AM) has grown considerably in the past decades and
industry has gained great benefits from this type of technology. The main advantages are:
geometrical freedom that allows the design of parts with complex shape, which are difficult
or impossible to produce by conventional technology; shortened design-to-product time;
customization and the possibility to use several materials in one process. Direct Metal Laser
Sintering (DMLS) is one of the most promising AM technologies that utilizes metal powders.
Due to the layer-by-layer nature of powder delivery used in DMLS, the drawbacks are:
surface quality and accuracy, high residual stress in as-built parts and porosity – all of which
depend on the powder material, process-parameters, scanning and building strategies. This
can result in a substantial deterioration of the mechanical properties of the products and their
performance characteristics. For this reason, it is very important to identify defective parts
before enrolling into service.
Non-destructive testing (NDT) is effective for detection of internal defects without causing
damage. NDT also covers a wide group of methods of analysis used to evaluate the properties
of a material. NDT techniques like visual, acoustic, ultrasonic, thermal, X-ray and 3Dcomputed
tomography (CT) inspections are now widely used for various industrial
applications. For the analysis of material properties and the detection of defects, each of these
methods uses different physical principles that have their advantages and disadvantages. In this study, some of the NDT techniques are evaluated in terms of their applicability to the
inspection of parts manufactured by DMLS technology: Visual, Ultrasonic, Computed
Tomography and Acoustic Emission inspection.
Artificial defects were used to determine the feasibility of each NDT method. DMLS samples
were produced containing a range of artificial defects. These samples were than subjected to
each method and the results compared. A comparison between the amount of defect
information obtained is made.
It was shown that the nature of the sample; shape, size, material and the type of defects
present plays a vital role in the selection of testing methods. Ultrasonic-Total Focus Method
indicated that some defects are present upon testing relatively big samples with simple
geometry. X-ray Computed Tomography showed some limitations with regard to the
possibilities and the amount of defect detail, the only drawback being the cost and time
involved. Acoustic Emission showed to be a promising method for production parts although
it requires an initial time investment; thereafter it is a simple and easy way of detecting
defective samples
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Microfluidic Investigations of Capillary Flow and Surface Phenomena in Porous Polymeric Media for 3D Printing
The advent of 3D Printing has invigorated research into metamaterials, synthetic composite material that produce properties generally not found in natural materials, requiring further studies into understanding the fundamental properties of these materials. This dissertation proposes a novel imaging technique to investigate the surface interactions occurring in an unsaturated packed porous polymeric powder bed experiencing a colloidal fluid penetrating the powder bed, specifically to characterize nanoparticle attachment to polymeric particles. Additionally, Washburn capillary rise studies provide quantitative information about the free energy of a surface, specifically, contact angle. Temperature dependent studies were performed to probe the impact of fluids and polymeric powders interactions in elevated temperatures. An unintentional advantage of this novel imaging technique is that the experiment is straightforward, cheap, and time efficient; aptly described as “frugal science.
\u3cem\u3eGRASP News\u3c/em\u3e, Volume 6, Number 1
A report of the General Robotics and Active Sensory Perception (GRASP) Laboratory, edited by Gregory Long and Alok Gupta
NASA Tech Briefs, September 1987
Topics include: NASA TU Services; New Product Ideas; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Fabrication Technology; Machinery; Mathematics and Information Sciences; Life Sciences