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Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Sciences appliquees, Applied sciences, Alliage Ti90Al6V4, Alloy-Ti90Al6V4, Alliage base titane, Titanium base alloys, Conception ingénierie, Engineering design, Concepción ingeniería, Condition opératoire, Operating conditions, Condición operatoria, Débit massique, Mass flow rate, Caudal masico, Epaisseur couche, Layer thickness, Espesor capa, Etude expérimentale, Experimental study, Forme libre, Free form, Forma libre, Métal, Metals, Méthode empirique, Empirical method, Método empírico, Plan expérience, Experimental design, Procédé dépôt, Deposition process, Procedimiento revestimiento, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Titane, Titanium, Tranchage, Slicing, Chapeado, Format STL, STL format, Formato STL, Design of Experiments, Freeform Fabrication, Laser Engineered Net Shaping, and Rapid Prototyping

Laser Engineered Net Shaping (LENS) is a rapid prototyping technology that can build complex, three-dimensional geometries in metal. It converts STL files to metal prototypes by slicing the file into two-dimensional layers of user-defined thickness and superimposing successive layers as they are built. The user must choose the layer thickness when slicing the file and must match the deposition to keep the laser in focus throughout the build-large mismatches can cause the build to fail. Because deposition is primarily controlled by build parameters, designed experiments are used to study the effect of select process parameters on deposition for Ti-6AI-4V. A simple relation between these build parameters and deposition is developed, using experimental results to determine empirical constants. Experimental results suggest that deposition can be related to the product of mass flow rate and energy per unit area through a power relationship, and could prove useful in estimating an appropriate layer thickness.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Appareillage et mise en oeuvre, Machinery and processing, Matières plastiques, Plastics, Divers, Miscellaneous, Couleur, Color, Electrophotographie, Electrophotography, Electrofotografía, Etude expérimentale, Experimental study, Estudio experimental, Impression laser, Laser printing, Impresión laser, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Thermoplastique, Thermoplastics, and Termoplástica

This paper reports on preliminary results involving an experimental rapid prototyping process known as 3-D laser printing. The system builds parts by repeatedly laser printing thermoplastic cross-sectional slice images of a part one on top of the next. With each new layer, the total build thickness increases until the part is complete. An interesting extension to this system involves the use of a color print engine to produce selectively colored parts. Conventional rapid prototyping processes generally do not allow this sort of selective coloring. Initial results indicate that the system has considerable potential and warrants continued investigation.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Transfert de chaleur, Heat transfer, Méthodes numériques et analytiques, Analytical and numerical techniques, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Assemblage et découpage thermique: aspects métallurgiques, Joining, thermal cutting: metallurgical aspects, Soudage, Welding, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Adhérence, Adhesion, Adherencia, Adhaesion, Aluminium, Aluminio, Amplitude vibration, Vibration amplitude, Amplitud vibración, Assemblage soudé, Welded joint, Ensamblaje soldado, Schweissverbindung, Basse température, Low temperature, Baja temperatura, Tieftemperatur, Condition opératoire, Operating conditions, Condición operatoria, Etat surface, Surface conditions, Estado superficie, Oberflaechenzustand, Etude expérimentale, Experimental study, Estudio experimental, Experimentelle Untersuchung, Forme libre, Free form, Forma libre, Interface solide solide, Solid solid interface, Interfase sólido sólido, Grenzschicht fest fest, Matériau composite, Composite material, Material compuesto, Verbundwerkstoff, Modélisation, Modeling, Modelización, Métal, Metal, Metalle, Méthode domaine temps fréquence, Time frequency domain method, Método dominio tiempo frecuencia, Méthode élément fini, Finite element method, Método elemento finito, Finite Element Methode, Propriété thermomécanique, Thermomechanical properties, Propriedad termomecánica, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Résistance électrique, Resistor, Resistencia eléctrica(componente), Soudage diffusion, Diffusion welding, Soldeo por difusión, Diffusionsschweissen, Soudage friction, Friction welding, Soldeo por fricción, Reibschweissen, Soudage ultrason, Ultrasound welding, Soldeo por ultrasonidos, Ultraschallschweissen, Soudure, Weld, Soldadura, Schweissnaht, Source chaleur, Heat source, Fuente calor, Freeform Fabrication, Multi-Material Adhesion, Rapid Prototyping, Ultrasonic Joining, Ultrasonic Manufacturing, and Ultrasonic Metal Welding

Ultrasonic rapid manufacturing (URM), a low-temperature solid freeform fabrication method capable of producing high-strength functional solid metal parts and multi-material composites, is based on ultrasonic welding (USW) of metals. The quality of the weld, a critical aspect of the URM process, depends on (a) the amount of mechanical energy applied, through an appropriate combination of welding parameters: vertical pressure, horizontal vibration frequency, amplitude, and welding time, (b) the resulting heat generation, and (c) temperature rise. This paper investigates the thermomechanical process aspects and provides insight into the heat generation and transient-temperature profile during a single weld cycle under the special welding conditions developed in this article and validated in the laboratory. The finite element model analysis of two layers of aluminum foil subjected to these welding conditions-with surface contact resistance calibrated by experiments-reveals a moderate temperature rise but one that is sufficient for metal bonding via vacancy diffusion.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Acier bas carbone, Low carbon steel, Acero bajo carbono, Basse température, Low temperature, Baja temperatura, Etat surface, Surface conditions, Estado superficie, Etude expérimentale, Experimental study, Estudio experimental, Haute température, High temperature, Alta temperatura, Laser CO2, CO2 laser, Machine vitesse élevée, High speed machine, Máquina gran velocidad, Matériau stratifié, Stratified material, Material estratificado, Modèle 2 dimensions, Two dimensional model, Modelo 2 dimensiones, Modèle 3 dimensions, Three dimensional model, Modelo 3 dimensiones, Moulage injection, Injection molding, Moldeo por inyección, Moulage transfert, Transfer molding, Moldeo por transferencia, Outillage rapide, Rapid tooling, Herramienta rapida, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Résine, Resins, and Resina

Laminated tooling is a relatively fast and simple method to make metal tools directly for injection molding or resin transfer molding in the rapid prototyping field. Metal sheets are usually cut, stacked, aligned, and joined. Joining of metal sheets is usually accomplished by brazing or soldering. In the joining process, all the metal sheet layers should be rigidly joined, and thus heat should be applied to the whole volume of the laminate. Therefore, furnace brazing or diffusion bonding processes are considered suitable in laminated tooling. In this study, a rapid laminated tooling system composed of a CO2 laser, a furnace, and a high-speed milling machine was developed. From the three-dimensional information of a product, slicing into two-dimensional contours was performed and low-carbon steel sheets were cut with the CO2 laser along the paths that were created from the slicing results. The metal sheets were joined by furnace brazing and by dip soldering. Furnace brazing was for relatively high-temperature tooling processes such as injection molding, and dip soldering was for low-temperature tooling processes such as reactive injection molding (RIM). Dip soldering was introduced as a new, simple, and fast joining process of steel laminates. In both joining methods, wetting experiments were performed to ensure the optimal values of the process parameters. Finally, laminate tools were machined with a high-speed milling machine to improve the surface quality.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Assemblage et découpage thermique: aspects métallurgiques, Joining, thermal cutting: metallurgical aspects, Soudage, Welding, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Acier inoxydable 316L, Stainless steel-316L, Acier inoxydable, Stainless steel, Acero inoxidable, Nichtrostender Stahl, Aluminium alliage, Aluminium alloy, Aluminio aleación, Aluminiumlegierung, Assemblage soudé, Welded joint, Ensamblaje soldado, Schweissverbindung, Condition opératoire, Operating conditions, Condición operatoria, Etat solide, Solid state, Estado sólido, Fester Zustand, Etude expérimentale, Experimental study, Estudio experimental, Experimentelle Untersuchung, Faisabilité, Feasibility, Practicabilidad, Forme libre, Free form, Forma libre, Mesure optique, Optical measurement, Medida óptica, Optisches Messen, Microscopie optique, Optical microscopy, Microscopía óptica, Optische Mikroskopie, Métal, Metal, Metalle, Processus fabrication, Production process, Proceso fabricación, Procédé dépôt, Deposition process, Procedimiento revestimiento, Beschichtungsverfahren, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Rugosité, Roughness, Rugosidad, Rauhigkeit, Résistance pelage, Peel strength, Resistencia pelado, Soudage ultrason, Ultrasound welding, Soldeo por ultrasonidos, Ultraschallschweissen, Soudure, Weld, Soldadura, Schweissnaht, Viabilité, Viability, Viabilidad, Additive Manufacturing, Free-Form Fabrication, Layered Manufacturing, Solid-State Welding, Stainless Steel, and Ultrasonic Consolidation

The viability of using 316L stainless steel in the ultrasonic consolidation process was examined in this work. Ultrasonic consolidation is an additive, free-form manufacturing process that employs ultrasonic welding and machining to form a part. The process ultrasonically joins layers of metal together by welding them one at a time. Once four layers of metal foil are welded together, welding is suspended and the system machines the part outline, and repeats this cycle until a component is completed. Experiments were conducted to determine the feasibility and processing parameters for ultrasonically welding stainless steel. Mechanical testing and optical microscopy were conducted. 316L stainless steel was successfully welded. Increasing welding amplitude and decreasing welding speed were the most effective way to increase weld peel strength. Unlike work in aluminum alloys, these experiments found no relationship between horn force and peel strength. Rough processing windows for ultrasonically welding 316L were identified.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Algorithme adaptatif, Adaptive algorithm, Algoritmo adaptativo, Intégration numérique, Numerical integration, Integración numérica, Machine 5 axes, Five axis machine, Maquina 5 ejes, Outil coupe, Cutting tool, Herramienta corte, Processus fabrication, Production process, Proceso fabricación, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Préparation gamme fabrication, Process planning, Preparación serie fabricación, Section variable, Variable section, Sección variable, Stratification, Estratificación, Système hybride, Hybrid system, Sistema híbrido, Système production, Production system, Sistema producción, Trajectoire optimale, Optimal trajectory, Trayectoria óptima, Tranchage, Slicing, Chapeado, Usinage, Machining, Mecanizado, Hybrid System, Layered Manufacturing, Process Planning, and Toolpath Generation

With the integration of multiaxis layered manufacturing and material removal (machining) processes, a hybrid system has more capability and flexibility to build complicated geometry with a single setup. Process planning to integrate the two different processes is a key issue. In this paper, an algorithm of adaptive slicing for a five-axis Laser Aided Manufacturing Process (LAMP) is summarized that can generate uniform and non-uniform thickness slices. A method to build a non-uniform (thickness) layer that utilizes two processes is presented, and an overall algorithm for integration is described. The newly developed algorithm implemented in the process planning helps the hybrid system build parts more efficiently.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Appareillage et mise en oeuvre, Machinery and processing, Matières plastiques, Plastics, Divers, Miscellaneous, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, ABS, Acrilonitrilo butadieno estireno copolímero, Analyse thermique, Thermal analysis, Análisis térmico, Condition opératoire, Operating conditions, Condición operatoria, Etude expérimentale, Experimental study, Estudio experimental, Frittage, Sintering, Sinterización, Modélisation, Modeling, Modelización, Polymère, Polymer, Polímero, Propriété mécanique, Mechanical properties, Propiedad mecánica, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Refroidissement, Cooling, Enfriamiento, Stratification, Estratificación, Technologie poudre, Powder technology, Machine dépose fil, Fused deposition modeling, and Depósito hilo FDM

The bonding quality among polymer filaments in the fused deposition modeling (FDM) process determines the integrity and mechanical properties of resultant prototypes. This paper investigates the bond formation among extruded acrylonitrile butadiene styrene (ABS) filaments in the FDM process. Thermal analysis of the FDM process resulted in an estimation of the cooling profile of the extruded filaments. Sintering experiments were carried out to evaluate the dynamics of bond formation between polymer filaments. Quantitative predictions of the degree of bonding achieved during the filament deposition process were made. The model was used to estimate the effects of different manufacturing parameters in the FDM process. Results suggest that better control of the cooling conditions may have strong repercussions on the mechanical properties of the final part fabricated using the FDM process.

Management economics, Gestion, économie, management, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Elasticité statique (thermoélasticité...), Static elasticity (thermoelasticity...), Static elasticity, Analyse structurale, Structural analysis, Análisis estructural, Equation constitutive, Constitutive equation, Ecuación constitutiva, Etat semi solide, Semi solid state, Estado semisolido, Forme libre, Free form, Forma libre, Matériau composite, Composite material, Material compuesto, Modélisation, Modeling, Modelización, Procédé dépôt, Deposition process, Procedimiento revestimiento, Prototypage rapide, Rapid prototyping, and Prototipificación rápida

Solid freeform fabrication (SFF) technologies have the ability to manufacture functional parts with locally controlled properties, which provides an opportunity for manufacturing a whole new class of products. To a certain extent, fused deposition modeling (FDM) has the potential to fabricate parts with locally controlled properties by changing deposition density and deposition orientation. To fully exploit this potential, this paper reports a study of the materials, the fabrication process, and the mechanical properties of FDM prototypes. Theoretical and experimental analyses of mechanical properties of FDM processes and prototypes were carried out to establish the constitutive models. A set of equations is proposed to determine the elastic constants of FDM prototypes. The models are then evaluated by experiments. An example of FDM prototype with locally controlled properties is provided to demonstrate the ideas.