Solder paste printing process modelling map

This paper presents work done in the modelling of solder paste printing, a crucial process in the reflow soldering of surface mounted electronic components. The map summarises the results of the experimental observations and theoretical models developed. In the mapping approach developed, information on the process models and modelling technique (including assumptions used), process and equipment parameters, physical sub-processes, process variables, and the process performance in terms of quality and/or defects are represented. The solder paste printing process is modelled as six different interacting sub-processes in the physical sub-processes layer, namely: pre-print paste treatment, squeegee deformation, paste roll in front of the squeegee, aperture filling, aperture emptying and paste slump. The sub-processes are linked together by the properties of the solder paste such as its flow history or theology in terms of the stress/strain history and the viscosity/time graph