Sharif Digital Repository

In this paper, a combined experimental and numerical investigation is described for powder compaction processes. It utilises material properties derived from experimental work as input for inelastic analysis of a finite element model. Numerical modelling of the powder compaction process is performed using a large-displacement finite element method. Powder material parameters, such as cohesion, internal friction angle and Young's modulus, were experimentally established as functions of relative density. These non-linear functions are incorporated into the inelastic analysis of the finite element model in order to establish model input parameters during different stages of compaction. Finally,... 

Inkjet printing of colloidal metals is an attractive method for direct patterning of electrically conductive structures and interconnects in electronic devices, owing to low-cost, low-waste and simplicity of the process. In the present work, mixtures of well-dispersed silver nanoparticles and ethylene glycol were prepared for the inkjet printing process. Three different surfactants including PVP, MSA and AOT were added to study the stability of the nanosilver colloids. The effect of high-intensity ultrasonic treatment and temperature on the rheological properties was investigated utilising a rheometer in plate-plate geometry. It is shown that the viscosity of the ink increases with...