Download or read book Electron Beam Curing of Composites written by Felipe Wolff-Fabris and published by . This book was released on 2011 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Electron beam curing technology for advanced composites has emerged as a credible and attractive alternative to thermal curing for most composite products. Technical advantages, such as aerospace structures, include curing at room temperature, using low-cost tooling, and the ability to fabricate large integrated structure including structures too large to fit inside autoclaves. Studies by aerospace companies have shown potential cost savings of 10-60% by using electron beam curing. In this book, both theoretical and practical aspects of electron beam curing of composites are presented, intending to build a bridge between the academic knowledge and the industrial applications."--Publisher.
Download or read book Electron Beam E Beam Processing as a Means of Achieving High Performance Composite Structures written by and published by . This book was released on 2001 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron-beam (E-beam) curing is among the key out-of-autoclave technologies being explored for future advanced composite and adhesive applications. E-beam irradiation curing is capable of rapid and through-thickness curing of composite samples up to 2-in thickness, eliminating the need for long cure cycles in the autoclave. However, current resin and adhesive chemistries are optimized for cure by thermal initiation, which involves slow ramps and long cure cycles, particularly for thermoset composites based on epoxides. Therefore, in order to provide improved performance in composite systems cured by E-beam irradiation, a program was undertaken to investigate performance and formulation effects in two E-beam curable systems. One system, a free-radical-cured acrylic system, introduces the concept of interpenetrating network structures as a means of meeting performance requirements in E-beam-processed composites. The second resin system incorporates cationic curing of epoxides induced through Lewis acid or cation generating initiators. Additionally, a new approach to toughened interpenetrating polymer networks (IPNs) based on simultaneous cure using both free-radical and cationic-cure mechanisms is proposed along with initial experimental characterizations. The results of formulation and processing modifications on key properties of adhesives, resins, and composites structures are demonstrated.
Download or read book Electron Beam E Beam Processing as a Means of Achieving High Performance Composite Structures written by James M. Sands and published by . This book was released on 2001-11-01 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron-beam (E-beam) curing is among the key out-of-autoclave technologies being explored for future advanced composite and adhesive applications. E-beam irradiation curing is capable of rapid and through- thickness curing of composite samples up to 2-in thickness, eliminating the need for long cure cycles in the autoclave. However, current resin and adhesive chemistries are optimized for cure by thermal initiation, which involves slow ramps and long cure cycles, particularly for thermoset composites based on epoxides. Therefore, in order to provide improved performance in composite systems cured by E-beam irradiation, a program was undertaken to investigate performance and formulation effects in two E-beam curable systems. One system, a free-radical-cured acrylic system, introduces the concept of interpenetrating network structures as a means of meeting performance requirements in E-beam- processed composites. The second resin system incorporates cationic curing of epoxides induced through Lewis acid or cation generating initiators. Additionally, a new approach to toughened interpenetrating polymer networks (IPNs) based on simultaneous cure using both free-radical and cationic-cure mechanisms is proposed along with initial experimental characterizations. The results of formulation and processing modifications on key properties of adhesives, resins, and composites structures are demonstrated.
Download or read book Advanced Low Cost Composite Curing With High Energy Electron Beams Phase 2 written by Daniel Goodman and published by . This book was released on 1998 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron Beam (EB) curing of resin and adhesive offers significant advantages for fabricating and bonding of fiber-reinforced polymer composites for ground vehicle structural components. The EB curing process reduces the time to cross-link the polymer matrix or the adhesive compared to conventional heat curing. The process allows curing at room temperature for high throughput and reduced residual stresses for good part fit-up. EB adhesive curing also prevents de-bonding of dissimilar materials that can occur during the cool-down cycle. As part of this SBIR, Science Research Laboratory (SRL) has developed resins, adhesives and electron gun technology for high-energy electron beam curing and bonding of composites. During Phase I, SRL developed B-stageable, EB-curable resins suitable for a high for the resin transfer molding I electron beam curing process. SRL also developed a costing model for this process and applied the model to one high-quantity part. During Phase II, SRL optimized and tested the novel resin system, and used the resins in production of EB-cured panels for the Army's Composite Armored Vehicle. SRL also developed novel EB-curable adhesives and demonstrated the advantages of EB curing of adhesives for automotive applications by bonding together test panels of the Chrysler Composite Concept Vehicle. Commercialization of EB curing in the automotive industry is continuing as part of SRL collaborations with Daimler-Chrysler and Ford. Because the properties of the B-stageable EB-curable resins were better than expected, and because of the processing advantages of B-staging, the aerospace community is also considering the use of these resins for aircraft parts. Resin and adhesive samples and associated design data have been requested by two groups at Boeing, and by designers at Lockheed Martin, Northrop Grumman and Raytheon/Hughes.
Download or read book Declaration du Roy en faveur de Monseigneur le Duc d Orleans Frere unique de Sa Majest et de Mr le Comte de Soissons written by and published by . This book was released on 1637 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron beam Curing of Thermoset Resins for Composites written by Thierry Glauser and published by . This book was released on 1999 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Beam Curing of Polymer Matrix Composites written by and published by . This book was released on 1998 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of the CRADA was to conduct research and development activities to better understand and utilize the electron beam PMC curing technology. This technology will be used to replace or supplement existing PMC thermal curing processes in Department of Energy (DOE) Defense Programs (DP) projects and American aircraft and aerospace industries. This effort involved Lockheed Martin Energy Systems, Inc./Lockheed Martin Energy Research Corp. (Contractor), Sandia National Laboratories, and ten industrial Participants including four major aircraft and aerospace companies, three advanced materials companies, and three electron beam processing organizations. The technical objective of the CRADA was to synthesize and/or modify high performance, electron beam curable materials that meet specific end-use application requirements. There were six tasks in this CRADA including: Electron beam materials development; Electron beam database development; Economic analysis; Low-cost Electron Beam tooling development; Electron beam curing systems integration; and Demonstration articles/prototype structures development. The contractor managed, participated and integrated all the tasks, and optimized the project efforts through the coordination, exchange, and dissemination of information to the project participants. Members of the Contractor team were also the principal inventors on several electron beam related patents and a 1997 R and D 100 Award winner on Electron-Beam-Curable Cationic Epoxy Resins. The CRADA achieved a major breakthrough for the composites industry by having successfully developed high-performance electron beam curable cationic epoxy resins for use in composites, adhesives, tooling compounds, potting compounds, syntactic foams, etc. UCB Chemicals, the world's largest supplier of radiation-curable polymers, has acquired a license to produce and sell these resins worldwide.
Download or read book The advantages of electron beam curing of fibre reinforced composites written by C. B. Saunders and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Interfacial Properties of Electron Beam Cured Composites written by and published by . This book was released on 1999 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of the CRADA are to: Confirm that fiber-resin adhesion is responsible for the observed poor shear properties; Determine the mechanism(s) responsible for poor adhesion between carbon fibers and epoxy resins after e-beam curing; Develop and evaluate resin systems and fiber treatments to improve the properties of e-beam cured, carbon-fiber-reinforced composites; and Develop refined methods for processing e-beam cured, carbon-fiber-reinforced composites.
Download or read book The Influence of Material and Process Parameters on High energy Electron Beam Curing of Polymer Composites written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Influence of Material and Process Parameters on High energy Electron Beam Curing of Polymer Composites written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High-energy electron beam (EB) curing of advanced composites is a novel alternative to conventional thermal processing. It offers the possibilities of both cost reduction and technical improvements when compared to autoclave curing. The purpose of this thesis is to present a critical examination of the process of EB curing, with the intent of developing a better understanding of its potential for commercial use. Specifically, this study describes EB curing, and then identifies and examines the influence of important material and process parameters on curing and material properties. A resin system consisting of a high-temperature epoxy and a cationic photoinitiator is investigated. The material and process parameters of radiant dose, initiator concentration, temperature, dose rate, and reinforcement are analysed for their effect on cure extent and glass transition temperature, Tg. Experimental investigation is performed by differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). Properties are also compared between EB and thermally cured samples of the identical resin formulation by mechanical testing. The most notable result of this research is th t incomplete curing (less than 80% cure extent) occurs for the epoxy formulation irradiated at room temperature, even at EB doses as high as 500 kGy. Also significant is that the ultimate cure extent is strongly influenced by the temperature and dose rate during processing. These results may curtail some of the proposed advantages of EB processing such as the ability to EB cure at a selectable temperature. Additional results are presented and discussed which are important to the further development of predictive models for high energy EB curing of composites.
Download or read book Electron Beam Curing of Polymer Matrix Composites CRADA Final Report written by and published by . This book was released on 1997 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major cost driver in manufacturing polymer matrix composite (PMC) parts and structures, and one of the elements having the greatest effect on their quality and performance, is the standard thermal cure process. Thermal curing of PMCs requires long cure times and high energy consumption, creates residual thermal stresses in the part, produces volatile toxic by-products, and requires expensive tooling that is tolerant of the high cure temperatures.
Download or read book The Design and Synthesis of Epoxy Matrix Composites Curable by Electron Beam Induced Cationic Polymerization written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-25 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several new series of novel, high reactivity epoxy resins are described which are designed specifically for the fabrication of high performance carbon fiber reinforced composites for commercial aircraft structural applications using cationic UV and e-beam curing. The objective of this investigation is to provide resin matrices which rapidly and efficiently cure under low e-beam doses which are suitable to high speed automated composite fabrication techniques such as automated tape and tow placement. It was further the objective of this work to provide resins with superior thermal, oxidative and atomic oxygen resistance. Crivello, James V. Langley Research Center
Download or read book Critical Parameters for Electron Beam Curing of Cationic Epoxies and Property Comparison of Electron Beam Cured Cationic Epoxies Versus Thermal Cured Resins and Composites written by and published by . This book was released on 1997 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electron beam curing of composites is a nonthermal, nonautoclave curing process offering the following advantages compared to conventional thermal curing: substantially reduced manufacturing costs and curing times; improvements in part quality and performance; reduced environmental and health concerns; and improvements in material handling. In 1994 a Cooperative Research and Development Agreement (CRADA), sponsored by the Department of Energy Defense Programs and 10 industrial partners, was established to advance electron beam curing of composites. The CRADA has successfully developed hundreds of new toughened and untoughened resins, offering unlimited formulation and processing flexibility. Several patent applications have been filed for this work. Composites made from these easily processable, low shrinkage material match the performance of thermal cured composites and exhibit: low void contents comparable to autoclave cured composites (less than 1%); superb low water absorption values in the same range as cyanate esters (less than 1%); glass transition temperatures rivaling those of polyimides (greater than 390 C); mechanical properties comparable to high performance, autoclave cured composites; and excellent property retention after cryogenic and thermal cycling. These materials have been used to manufacture many composite parts using various fabrication processes including hand lay-up, tow placement, filament winding, resin transfer molding and vacuum assisted resin transfer molding.
Download or read book Carbon fiber acrylated epoxy composites an application for high energy electron beam curing written by C. B. Saunders and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radiation Curing written by R. S. Davidson and published by iSmithers Rapra Publishing. This book was released on 2001 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a very readable review on the exciting, advancing technology of radiation curing. The principles upon which the technology is based, the equipment that is used and the materials which make up a radiation curable formulation are described. The applications of radiation curing are set to expand. Current applications for radiation curing are all discussed in this review, with principle material types outlined. The review is well referenced to facilitate further reading. It is accompanied by around 400 abstracts from the Rapra Polymer Library database, most of which are cited in the d104.
Download or read book Electron beam curing of aramid fiber reinforced composites written by C. B. Saunders and published by . This book was released on 1991 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
