3 resultados para Rapid Technologie
em Greenwich Academic Literature Archive - UK
Resumo:
The electric car, the all electric aircraft and requirements for renewable energy are prime examples of potential technologies needing to be addressed in the world problem of global warming/carbon emission etc. Power electronics are fundamental for the underpinning of these technologies and with the diverse requirements for electrical configurations and the range of environmental conditions, time to market is paramount for module manufacturers and systems designers alike. This paper presents a 'virtual' design methodology together with theoretical and experimental results that demonstrate enhanced product design with improved reliability, performance and cost value within competitive schemes.
Resumo:
The curing of a thermosetting polymer materials utilized on micro-electronics packaging applications can be performed using microwave systems. The use of microwave energy enables the cure process to be completed more rapidly than with alternative approaches due to the ability to heat volumetrically. Furthermore, advanced dual-section microwave systems enable curing of individual components on a chip-on-board assembly. The dielectric properties of thermosetting polymer materials, commonly used in microelectronics packaging applications, vary significantly with temperature and degree of cure. The heating rate within a material subjected to an electric field is primarily dependant on the dielectric loss properties of the material itself. This article examines the variation in dielectric properties of a commercially available encapsulant paste with frequency and temperature and the resulting influence on the cure process. The 'FAMOBS' dual section microwave system and its application to microelectronics manufacture are described. The measurement of the dielectric properties of 'Henkel EO1080' encapsulant paste uses a commercially available 'dielectric probe kit' and is described in this paper. The FAMOBS heating system is used to encapsulate a small op-amp chip. A numerical model formulated to assess the cure process in thermosetting polymer materials under microwave heating is outlined. Numerical results showing that the microwave processing systems is capable of rapidly and evenly curing thermosetting polymer materials are presented.
Resumo:
The rapid prototyping (RP) process is being used widely with great potential for rapid manufacturing of functional parts. The RP process involves translation of the CAD file to STL format followed by slicing of the model into multiple horizontal layers, each of which is reproduced physically in making the prototype. The thickness of the resulting slices has a profound effect on the surface finish and build time of the prototype. The purpose of this paper is to show the effects of slice thickness on the surface finish, layering error, and build time of a prototype, as well as to show how an efficient STL file can be developed. Three objects were modeled and STL files were generated. One STL file for each object was sliced using different slice thicknesses, and the build times were obtained. Screenshots were used to show the slicing effect on layering error and surface finish and to demonstrate the means to a more efficient STL file. From the results, it is clear that the surface finish and build time are important factors that are affected by slice thickness