Thermo-mechanical process modelling of industrially pultruded parts having UD and CFM layers

Numerical process simulation of an industrially pultruded rectangular hollow profile is presented. The product contains the continuous filament mat (CFM) and the uni-directional(UD) roving layers made of glass/polyester. The distortion and stress evolutions together with the temperature and degree of fields are predicted by the simulation tool developed by the authors. The predicted deformation pattern at the end of the process is found to agree quite well with the one for the real pultruded part in a commercial pultrusion company. A parametric study is also performed based on the total volumetric shrinkage of the resin system during curing. The process induced residual stresses are calculated in the in-plane directions which have the potential to influence the internal stress levels during the service loading condition

Improvement in surface characterisitcs of polymers for subsequent electroless plating using liquid assisted laser processing

Metallization of polymers is a widely used process in the electronic industry that involves their surface modification as a pre-treatment step. Laser-based surface modification is one of the commonly used techniques for polymers due to its speed and precision. The process involves laser heating of the polymer surface to generate a rough or porous surface. Laser processing in liquid generates superior surface characteristics that result in better metal deposition. In this study, a comparison of the surface characteristics obtained by laser processing in water vis-à-vis air along with the deposition characteristics are presented. In addition, a numerical model based on the finite volume method is developed to predict the temperature profile during the process. Based on the model results, it is hypothesized that physical phenomena such as vapor bubble generation and plasma formation may occur in the presence of water, and it is because of these effects that causes an increase in surface porosity