Conduction mechanisms in contaminant layers on printed circuit boards : J. R. White. IBM Journal of Research and Development, 37(2), 243 (1993)

Abstract

As part of an extensive computer-aided engineering investigation, a comprehensive three-dimensional finite-element study is made of the critical components of a proposed design of the wheel-assembly of a centrifugal-peening machine.Throughout the investigation, the solid modelling facility of SDRC (GEOMOD) was utilised interactively to create the different geometries of the critical components of the wheel-assembly. Prior to the analysis, these geometries were transferred to the pre-processor (SUPERTAB) for model creation, mesh definition and model checking aspects. The appropriateloads and imposed restraints were also applied interactively.Both structural stress analysis and dynamic response studies were performed using a general purpose finite-element suite of programs known as SUPERB. The results of the structural stress-analysis investigations reveal that the current designs are mostly under-stressed and that a large saving in material can be achieved by reducing the thicknesses of the critical components, without compromising their structural integrity. The resulting modified geometries of the wheel-assembly were also subjected to dynamic response studies. The results indicate that no vibration problems will be experienced by the assembly either at or near to the proposed running speed of the machine of 3000 rev/min.