Browsing by Subject "additive manufacture"
Now showing 1 - 6 of 6
- Results Per Page
- Sort Options
Item Additive Manufacture of Large Structures: Robotic or CNC Systems?(University of Texas at Austin, 2015) Bandari, Yashwanth K.; Williams, Stewart W.; Ding, Jialuo; Martina, FilomenoAdditive manufacture of metre scale parts requires direct feed processes such as blown powder or wire feed combined with lasers or arcs. The overall system can be configured using either a robotic or Computer Numerical Controlled (CNC) gantry system. There are many factors that determine which of these is best and this will be presented in this paper. Some factors are inherent to the specific process type such as accuracy/resolution and any requirement for reorientation of the feedstock and heat source. Other factors depend on the particular application including material type, shielding options, part size/complexity, required build strategies and management of distortion. Further considerations include the incorporation of ancillary processes such as cold work, machining or inspection. The relative influence of these factors will be discussed. Cost implications for the different approaches will be highlighted based upon the type of process being utilized. Examples are provided where both robotic and CNC options have been evaluated and the best solution found.Item The Application of Composite Through-Thickness Assessment to Additively Manufactured Structures(University of Texas at Austin, 2017) Bitar, Isam S.; Aboulkhair, Nesma T.; Leach, RichardThis study looks into the applicability of through-thickness assessment to additive manufacturing (AM) carbon-fibre reinforced polymers (CFRPs). The study utilised a material extrusion printer that uses fused filament fabrication and composite filament fabrication technologies to manufacture functionally-graded polymer and composite polymer parts. The matrix material of choice was nylon 6. Samples were printed exploring a range of reinforcement volume content. In summary, this study presents an assessment of the applicability of through-thickness testing to AM CFRP specimens and provides a performance comparison between AM composite through-thickness properties and the properties of equivalent CM CFRP specimens.Item Approaches to Geometric Data Analysis on Big Area Additively Manufactured (BAAM) Parts(University of Texas at Austin, 2016) Dreifus, G.D.; Jin, Y.; Ally, N.; Post, B.K.The promise of additive manufacturing is that a user can design and print complex geometries that are very difficult, if not impossible, to machine. The capabilities of 3D printing are restricted by a number of factors, including properties of the build material, time constraints, and geometric design restrictions. In this paper, a thorough accounting and study of the geometric restrictions that exist in the current iteration of additive manufacturing (AM) fused deposition modeling (FDM) technologies on a large scale are discussed. Offline and online methodologies for collecting data sets for qualitative analysis of large scale AM, in particular Oak Ridge National Laboratory’s (ORNL) big area additive manufacturing (BAAM) system, are summarized. In doing so, a survey of tools for designers and software developers is provided. In particular, strategies in which geometric data can be used as training sets for smarter AM technologies in the future are explained.Item Comparison of Fatigue Performance Between Additively Manufactured and Wrought 304L Stainless Steel Using a Novel Fatigue Test Setup(University of Texas at Austin, 2019) Parvez, M.M.; Chen, Y.; Newkirk, J.W.; Liou, F.F.In this research, a novel adaptive controlled fatigue testing machine was designed for bending type high cycle fatigue test. A unique dual gauge section Krouse type mini specimen was designed for simply supported transverse bending. Displacement controlled fatigue tests were implemented using an electromechanical actuator. The variation in the control signal and load observed during the test provides unique insights into realizing the deterioration of the specimen due to fatigue. These analyses were utilized to compare the fatigue performance of wrought and additively manufactured 304L stainless steel. The influence of the build direction on fatigue performance was also investigated by testing specimens with 0, 45, and 90 degrees build direction. These comparisons were carried out at different levels of displacement amplitude.Item Hypervelocity Impact of Additively Manufactured A356/316L Interpenetrating Phase Composites(University of Texas at Austin, 2017) French, M.R.; Yarberry, W.A. III; Pawlowski, A.E.; Shyam, A.; Splitter, D.A.; Elliott, A.M.; Carver, J.K.; Cordero, Z.C.We have examined the hypervelocity impact response of targets made from monolithic A356 and 316L stainless steel, as well as an additively manufactured A356/316L interpenetrating phase composite. 1.9 mm diameter spherical projectiles made from 2017 aluminum were fired at velocities of 5.9-6.1 km/s, allowing for the observation of multiple types of macro- and microstructural damage within each target. The macroscopic cratering damage to the A356/316L composite resembles that of the A356, but observations of both the cross section and the microstructural damage suggest that the A356/316L composite may be more resistant to spalling than A356 shielding with the same areal density.Item Technique for Processing of Continuous Carbon Fibre Reinforced PEEK for Fused Filament Fabrication(University of Texas at Austin, 2019) Pu, Jing; Saleh, Ehab; Ashcroft, Ian; Jones, Arthur3D printing of light-weight and mechanically-strong structures facilitates several applications. 3D printing of continuous carbon fibre reinforced polyetheretherketone (PEEK) presents exciting possibilities as the high stiffness and strength of the high-performance plastic PEEK reinforced with carbon fibre are paired with the agility of the 3D printing process. The Fused Filament Fabrication (FFF) process is used to print these parts, and a pultrusion system was designed and used to produce the filaments since they are not commercially available. This paper describes the design and construction of a pultrusion system within a wider project on carbon fibre reinforced PEEK FFF printing. This system is then used to produce the FFF filament with pultrusion speed and temperature optimisation.