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Articles 1 - 7 of 7
Full-Text Articles in Mechanical Engineering
In Silico Analysis Of Advanced Processing Methods For Light-Weight Alloys Powders, Marjan Nezafati
In Silico Analysis Of Advanced Processing Methods For Light-Weight Alloys Powders, Marjan Nezafati
Theses and Dissertations
Light-weight Al and Mg-based metal-matrix nanocomposites (MMNCs) are lauded as one of the most promising structural materials for vehicle, military, and construction applications. These MMNCs are often synthesized using the powder metallurgy (PM) process under liquid nitrogen cryogenic environments to control the grain sizes. It is believed that proper incorporation of the nitrogen species into the bulk lattice during processing could strongly enhance the mechanical properties of MMNCs by forming N-rich dispersoids. In this work, using the density-functional theory (DFT), the adsorption, absorption and diffusion behavior of nitrogen molecule/atoms have been studied and related to t Al and Mg MMNC …
Microstructure And Mechanical Properties Of Selective Laser Melted Superalloy Inconel 625., Md Ashabul Anam
Microstructure And Mechanical Properties Of Selective Laser Melted Superalloy Inconel 625., Md Ashabul Anam
Electronic Theses and Dissertations
Selective Laser Melting (SLM), a powder based Additive Manufacturing (AM) process, has gained considerable attention in the aerospace, biomedical and automotive industries due to its many potential benefits, such as, capability of fabricating complex three-dimensional components, shortened design to product time, reduction in process steps, component mass reduction and material flexibility. This process uses metallic powder and is capable of fabricating complex structures with excellent microstructure which make SLM not only an improvement over other manufacturing processes but also innovative material processing technology. Inconel 625, a nickel-based super alloy is widely popular in aerospace, chemical and nuclear industries. This alloy …
Modeling And Validations Of Control Parameters For Material Extrusion-Based Additive Manufacturing Of Thixotropic Aluminum Alloys., Lars Herhold
Electronic Theses and Dissertations
Additive Manufacturing (AM) with metals has been accomplished mainly through powder bed fusion processes. Initial experiments and simulations using Material Extrusion Additive Manufacturing (MEAM) have been performed by various researchers especially using low melting alloys. Recently Stratasys Inc. submitted a patent application for the use of their Material Extrusion technology also called Fused Deposition Modeling (FDM) where they describe the process using thixotropic semi-solid alloys. Currently this process using semi-solid, engineering type alloys such as A356 or THIXALLOY 540 aluminum have not been researched to evaluate the control parameters. This research combines the in-depth knowledge of applying thixotropic semi-solid aluminum …
Ultrasonic Nondestructive Evaluation Of Metal Additive Manufacturing., Venkata Karthik Nadimpalli
Ultrasonic Nondestructive Evaluation Of Metal Additive Manufacturing., Venkata Karthik Nadimpalli
Electronic Theses and Dissertations
Metal Additive Manufacturing (AM) is increasingly being used to make functional components. One of the barriers for AM components to become mainstream is the difficulty to certify them. AM components can have widely different properties based on process parameters. Improving an AM processes requires an understanding of process-structure-property correlations, which can be gathered in-situ and post-process through nondestructive and destructive methods. In this study, two metal AM processes were studied, the first is Ultrasonic Additive Manufacturing (UAM) and the second is Laser Powder Bed Fusion (L-PBF). The typical problems with UAM components are inter-layer and inter-track defects. To improve the …
Fabrication Of 3d Conjugated Polymer Structures Via Vat Polymerization Additive Manufacturing, Andrew T. Cullen
Fabrication Of 3d Conjugated Polymer Structures Via Vat Polymerization Additive Manufacturing, Andrew T. Cullen
Electronic Thesis and Dissertation Repository
Conjugated polymers are a class of electromechanically active materials that can produce motion in response to an electric potential. This motion can be harnessed to perform mechanical work, and therefore these materials are particularly well suited for use as sensors and actuators in microelectromechanical systems. Conventional methods to fabricate conjugated polymer actuators result in planar morphologies that limit fabricated devices to simplistic linear or bending actuation modes. To overcome this limitation, this work develops a conjugated polymer formulation and associated additive manufacturing method capable of realizing three-dimensional conductive polymer structures. A light-based additive manufacturing technique known as vat polymerization is …
Selective Laser Melting Of Ni-Rich Niti: Selection Of Process Parameters And The Superelastic Response, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ehsan Saghaian, Ahmadreza Jahadakbar, Haluk E. Karaca, Mohammad Elahinia
Selective Laser Melting Of Ni-Rich Niti: Selection Of Process Parameters And The Superelastic Response, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ehsan Saghaian, Ahmadreza Jahadakbar, Haluk E. Karaca, Mohammad Elahinia
Mechanical Engineering Faculty Publications
Material and mechanical properties of NiTi shape memory alloys strongly depend on the fabrication process parameters and the resulting microstructure. In selective laser melting, the combination of parameters such as laser power, scanning speed, and hatch spacing determine the microstructural defects, grain size and texture. Therefore, processing parameters can be adjusted to tailor the microstructure and mechanical response of the alloy. In this work, NiTi samples were fabricated using Ni50.8Ti (at.%) powder via SLM PXM by Phenix/3D Systems and the effects of processing parameters were systematically studied. The relationship between the processing parameters and superelastic properties were investigated …
Bio-Mimetic Design With 3d Printable Composites, Ramya Mitra Patnam Damodaram
Bio-Mimetic Design With 3d Printable Composites, Ramya Mitra Patnam Damodaram
Electronic Theses and Dissertations
Weight and stiffness are key factors in the advancement of materials and parts for use in numerous industries. Lightweight cellular structures are broadly utilized for this reason. However, these structures must satisfy several key constraints: they should be light yet structurally safe, sustainable in different loading conditions, resource efficient and easy to maintain. Bio-inspired materials/structures which results in desirable material features are a significant inspiration for engineered cellular structures. Cellular structures can be designed to have multifunctional properties along with lightweight characteristics. Currently, these structures with high strength to weight ratio are widely applied in many fields such as automotive, …