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Wire sweep has been recognized as one of the major defects in encapsulation of electronic components by transfer molding. The phenomenon is very complicated as it is sensitive to a large number of parameters. lit this experimental work, where a 160L QFP package used as the test vehicle, the detailed time-dependent wire displacement is measured for the following two different flow initial conditions: (i) the wire is immersed in the liquid and is displaced due to the acceleration of the flow from rest to the steady-state velocity, and (ii) the wire is surrounded by the ambient air and is displaced first due to the passage of the liquid front and then due to the hydrodynamic load. Significant differences have been observed,between the two cases, with important implications for analytical and numerical studies of wire sweep.

Wire sweep has been recognized as one of the major defects in encapsulation of electronic components by transfer molding. The phenomenon is very complicated as it is sensitive to a large number of parameters. lit this experimental work, where a 160L QFP package used as the test vehicle, the detailed time-dependent wire displacement is measured for the following two different flow initial conditions: (i) the wire is immersed in the liquid and is displaced due to the acceleration of the flow from rest to the steady-state velocity, and (ii) the wire is surrounded by the ambient air and is displaced first due to the passage of the liquid front and then due to the hydrodynamic load. Significant differences have been observed,between the two cases, with important implications for analytical and numerical studies of wire sweep.

This thesis treats various aspects of structural polymercomposites in aircraft applications. The mechanical performanceand quality of resin transfer molded (RTM) carbon fiberreinforced epoxy composites is studied. In a first part, the influence of manufacturing process parameters on the mechanicalbehavior of laminates is experimentally investigated. A number of process parameters are used as variables and performance ismeasured in terms of tensile and compressive strength as wellas interlaminar fracture toughness. The process parameters are concluded to have little affect on the measured properties. In a second part, the quality and structural performance of an entirely co-cured RTM manufactured aircraft control surfacedemonstrator is investigated. A series of quasi staticstructural tests using distributed loading is performed. Experimental results are compared with finite element analysis. Effects of impact damage on the performance are also studied.Good agreement is obtained between the predictions and the experiments. A nondestructive method for determination of elasticmaterial properties of orthotropic plates using naturalfrequencies is developed and verified. Finite elementcalculations of the natural frequencies of the plate are matched to experimentally determined frequencies using theelastic constants as variables. The method is successfully verified even for nontrivial specimen geometries with cornersingularities. Emphasis is on practical utilization ofknowledge about numerical and modeling errors as well asexperimental uncertainties. The optimal design of a thin orthotropic wing subject toaeroelastic constraints is studied using numerical methods andverified in low speed wind tunnel testing. The flutter speed ofthe wing is maximized using the laminate orientation asvariable. Further, the problem of increasing the flutter speed to a prescribed value using minimal amount of additional concentrated masses on a fixed wing design is investigated. The main objec, QC 20100511

The various considerations underlying the specification and characterization of three-dimensional orientation distributions in moldings of short fiber reinforced polymers are discussed. The recommended treatment resolves the overall complex orientation pattern into distributions on a macroscopic and microscopic scale. Some examples, including the effects of molding conditions, are given for an end-gated rectangular bar plunger molded from fiberglass reinforced epoxy., Report on Monsanto/Washington Univ., ONR/ARPA Association High Performance Composites Program. See also AD779907. Sponsored in part by DARPA.

In an extension of the experiments performed on the compacted flow of a glass fiber- filled epoxy resin through a conical converging channel under a high pressure, this study examines the orientability of the fibers as the suspension flows into an expty mold cavity. The tensile properties of molded rods of 1/46 to 1/26 diameter reflect the level of orientation produced. Both the fiber orientability and the resulting orien- tation distribution depend strongly on the rate of elongation. The molded-in orientation distribution is also determined by the extent of convergence. Convergence angle, viscosity, and fiber length are secondary variables. The results indicate that fibers can be oriented to within 20 of the flow axis by this technique in order to maximize mechanical performance. The anomalous dependence on the rate of elongation is thought to result from the high voidate in the material during flow., See also report dated 5 Apr 1974, AD776591.

Several aspects of composite structure that affect the mechanical performance of polymers reinforced with short fibers are fiber length, fiber concentration, void content, dispersion of fibers, fiber orientation, and wetting. This report describes the dependence of these structural variables on the molding compound composition and on the processing conditions for flow (plunger) moldings of epoxy resin reinforced with short glass fibers. The methods used in this study for characterizing the composite structure are also presented. Since the primary structural variables mentioned above cannot in practice be changed independently, the measured tensile strengths and ultimate elongations of molded specimens are correlated directly with the preparation techniques and processing conditions used in their fabrication. It is found that voids, wetting, and dispersion are not critical when the fibers are properly aligned into the direction of highest stress. The fibers must be equal to or longer than one-eighth of an inch to sustain high loads in the epoxy system studied., Report on Mansanto/Washington Univ., ONR/ARPA Association project development of High Performance Composites.

Tato diplomová práce se zabývá způsoby pouzdření integrovaných obvodů a modulů a to především při použití levných a nehermetických pouzder. Součástí je také na základě zadaných informací a získaných teoretických poznatků návrh testovacího vzorku, který je určen k zapouzdření technologií fluidizace. Na základě výsledků testovacích metod bude nastíněno, kam dál se bude technologie uchylovat., This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.

Tato diplomová práce se zabývá způsoby pouzdření integrovaných obvodů a modulů a to především při použití levných a nehermetických pouzder. Součástí je také na základě zadaných informací a získaných teoretických poznatků návrh testovacího vzorku, který je určen k zapouzdření technologií fluidizace. Na základě výsledků testovacích metod bude nastíněno, kam dál se bude technologie uchylovat., This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.

Tato diplomová práce se zabývá způsoby pouzdření integrovaných obvodů a modulů a to především při použití levných a nehermetických pouzder. Součástí je také na základě zadaných informací a získaných teoretických poznatků návrh testovacího vzorku, který je určen k zapouzdření technologií fluidizace. Na základě výsledků testovacích metod bude nastíněno, kam dál se bude technologie uchylovat., This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.

Tato diplomová práce se zabývá způsoby pouzdření integrovaných obvodů a modulů a to především při použití levných a nehermetických pouzder. Součástí je také na základě zadaných informací a získaných teoretických poznatků návrh testovacího vzorku, který je určen k zapouzdření technologií fluidizace. Na základě výsledků testovacích metod bude nastíněno, kam dál se bude technologie uchylovat., This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.

Tato diplomová práce se zabývá způsoby pouzdření integrovaných obvodů a modulů a to především při použití levných a nehermetických pouzder. Součástí je také na základě zadaných informací a získaných teoretických poznatků návrh testovacího vzorku, který je určen k zapouzdření technologií fluidizace. Na základě výsledků testovacích metod bude nastíněno, kam dál se bude technologie uchylovat., This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.

Tato diplomová práce se zabývá způsoby pouzdření integrovaných obvodů a modulů a to především při použití levných a nehermetických pouzder. Součástí je také na základě zadaných informací a získaných teoretických poznatků návrh testovacího vzorku, který je určen k zapouzdření technologií fluidizace. Na základě výsledků testovacích metod bude nastíněno, kam dál se bude technologie uchylovat., This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.