Search Results for laser projection interface

Continuous fiber composite materials offer dramatic opportunities for producing lightweight laminates with tremendous performance capabilities. This article describes the kinematics of fabric deformation and explains the algorithms used in draping simulation. It discusses the basic components, such as laminate and ply, of continuous fiber composite. The article provides information on the core sample and ply analysis. It details producibility, flat-pattern evaluations, and laminate surface offset. The article discusses various interfaces, such as the structural analysis interface, the resin transfer molding interface, the fiber placement and tape-laying interface, and the laser projection interface.

This article focuses on four industrial additive manufacturing approaches that are used to create polymer parts. The first section focuses on material extrusion, providing information on lumped-parameter material flow models and higher-fidelity models developed to estimate temperature distribution. The second section covers polymer powder-bed sintering/ fusion, discussing the different levels of scale used to address modeling and the impact of process settings: thermodynamics at the powder-bed surface, consolidation of adjacent particles in the fusion process, and fusion and molecular-level behavior within particles. The third section on vat photopolymerization (VPP) discusses two primary approaches to modeling VPP processes, namely a lumped-parameter approach to estimate cured regions in the vat, known as the Jacobs model, and a high-fidelity, continuum approach that uses finite-element methods. The final section is devoted to material jetting, focusing on simulations used to study droplet generation at the nozzle and droplet impact.

Microjoining methods are commonly used to fabricate medical components and devices. This article describes key challenges involved during microjoining of medical device components. The primary mechanisms used in microjoining for medical device applications include microresistance spot welding (MRSW) and laser welding. The article illustrates the fundamental principles involved in MRSW and laser welding. The article presents examples of various microjoining methods used in medical device applications, including pacemaker and nitinol microscopic forceps.

Powder-bed additive manufacturing (AM) processes are some of the most commonly used techniques, necessitating the accurate measurement of powder flowability properties. This article discusses some powder flow tests that occur in powder-bed AM machines. These include the Hall/Carney flow test, bulk/tap density, rheometer, and the revolving or rotating drum technique. The three categories of powder properties that are available from rheometer experiments are discussed: bulk, dynamic flow, and shear properties. The article also describes the basic principles and applications of micro-X-ray computed tomography in studying powder porosity characteristics nondestructively.

This article discusses the fundamentals and operating principles of the following acoustic microscopy methods: scanning laser acoustic microscopy, C-mode scanning acoustic microscopy, and scanning acoustic microscopy. It describes the applications of acoustic microscopy for detecting defects in metals, ceramics, glasses, polymers, and composites with examples.

This article provides an overview of the adoption of additively manufactured materials in dentistry. It discusses the practical workflows of a three-dimensional printing technology, vat photopolymerization. Three subgroups of the vat photopolymerization process are laser beam or classic stereolithography apparatus (SLA), direct light processing, and liquid-crystal-display-masked SLA. The article covers two subgroups of 3D printing resins-based appliances, namely intraoral and extraoral appliances. Information on various types of dental appliances and the fabrication of in-office appliances is provided. The article also reviews fourth-dimension printing and discusses the applications of the personalized care model in medicine and dentistry.

Vat polymerization is a form of three-dimensional (3D) printing. Historically, it is the oldest additive manufacturing technique, with the development of stereolithography apparatus (SLA) by Charles Hull in 1986. This article outlines the various forms of vat polymerization techniques used for biomedical applications. Due to the complex nature of this printing process, many key print parameters and material properties need to be considered to ensure a successful print. These influential parameters are addressed throughout the article to inform the reader of the considerations that should be taken when using the vat polymerization technique. The article provides information on vat polymerization printer setup, the photo-cross-linking mechanism, and considerations using vat polymerization. In addition, it outlines and discusses the advancements of vat polymerization in the biomedical industry.

Properly designed beam-delivery optics is essential to quality of the beam acting on the workpiece and to the economics of the manufacturing process. This article describes the design considerations of laser beam delivery optics. It also reviews the manufacturing economics and presents two case studies of typical economic environments found in laser welding applications.

This article is a compilation of definitions for terms related to welding fundamentals and all welding processes. The processes include arc and resistance welding, friction stir welding, laser beam welding, explosive welding, and ultrasonic welding.

This article overviews the classification of welding processes and the key process embodiments for joining by various fusion welding processes: fusion welding with chemical sources for heating; fusion welding with electrical energy sources, such as arc welding or resistance welding; and fusion welding with directed energy sources, such as laser welding, electron beam welding. The article reviews the different types of nonfusion welding processes, regardless of the particular energy source, which is usually mechanical but can be chemical, and related subprocesses of brazing and soldering.

Although laser stir welding (LSW) is applied to various metallic systems, it is especially appropriate to laser beam welding (LBW) of aluminum, because liquid aluminum possesses significantly less surface tension and viscosity than most common metal alloys, which results in greater fluidity of the molten pool. This article schematically illustrates the keyhole instability in LBW and describes the process details of LSW. Representative macrographs of butt, lap, and fillet welds produced using the LBW and LSW processes are presented. The article discusses the laser welding technologies having a large impact on the ability to apply LSW in production. It concludes with information on the industrial applications of LSW.

This article discusses the basic operating principles, industrial applications, and advantages as well as the parameters influencing the process of laser-induced forward transfer (LIFT) of solid materials, liquid materials, laser-absorbing layers, intact structures, and metallic 3D microstructures in additive manufacturing.

This article reviews the emerging manufacturing technology that is alternatively called additive manufacturing (AM), direct digital manufacturing, free-form fabrication, three-dimensional (3-D) printing, and so on. It provides a broad contextual overview of metallic AM. The article focuses on the mechanical properties of AM-processed Ti-6Al-4V, IN-625, and IN-718. The development of closed-loop, real-time, sensing, and control systems is essential to the qualification and advancement of AM. This involves the development of coupled process-microstructural models, sensor technology, and control methods and algorithms. AM has the potential to revolutionize the global parts manufacturing and logistics landscape. It enables distributed manufacturing and the productions of parts on demand while offering the potential to reduce cost, energy consumption, and carbon footprint. The article explores the materials science, processes, and business considerations associated with achieving these performance gains. It concludes that a paradigm shift is required to fully exploit AM potential.

This article covers defect formation and classification, followed by a brief description of the most common nondestructive testing (NDT) methods used for postbuild inspection. Descriptions of the established and emerging NDT techniques for in-process monitoring (IPM) and in-process inspection (IPI) in additive manufacturing (AM) also are provided, highlighting the advantages and limitations. The article concludes with a list of the main NDT methods and techniques used. As qualification and certification of AM parts is an urgent matter for the AM industry, a description of the current work carried out for developing standards is also included.

This article introduces the principal methodologies and some advanced technologies that are being applied for nondestructive evaluation (NDE) of fiber-reinforced polymer-matrix composites. These include acoustic emission, ultrasonic, eddy-current, computed tomography, electromagnetic acoustic transducer, radiography, thermography, and low-frequency vibration methods. The article also provides information on NDE methods commonly used for metal-matrix composites.

This article introduces the principal methodologies and some technologies that are being applied for nondestructive evaluation of composite materials. These include ultrasonic testing (UT), air-coupled UT, laser UT, ultrasonic spectroscopy, leaky lamb wave method, acousto-ultrasonics, radiography, X-ray computed tomography, thermography, low-frequency vibration methods, acoustic emission, eddy current testing, optical holography, and shearography. The article presents some examples are for fiber-reinforced polymer-matrix composites. Many of the techniques have general applicability to other types of composites such as metal-matrix composites and ceramic-matrix composites.

This article presents a detailed account of the welding parameters, equipment needed, applications, advantages, limitations, and the process variables affecting various types of resistance welding operations, namely, resistance spot welding, resistance seam welding, resistance projection welding, and flash welding.

This article discusses the advantages, disadvantages, applications, and selection criteria of various technologies and transduction modalities that can generate and detect ultrasonic waves. These include piezoelectric transducers, electromagnetic acoustic transducers (EMATs), laser ultrasound phased array transducers, magnetostriction transducers, and couplants. The article discusses four basic types of search units with piezoelectric transducers. These include the straight-beam contact type, the angle-beam contact type, the dual-element contact type, and the immersion type. The article concludes with information on immersion or contact type focused search units.