Boundary value of rheological properties of solder paste

This work has been focused on viscosity and rheological measurement of some solder pastes as non-Newtonian. The results of the analysis show that increasing amount of metal powder content in solder paste show on influences of rheology changes of the solder paste. It is known that viscosity increases with increasing metal content. Aim of this work was determination of boundary value of viscosity and rheological properties without losses of thixotropy and pseudo plastic character. This typical feature of non-Newton liquid is important for better understanding of philosophy for high quality of solder paste deposition. Significant differences between the results were observed, which demonstrate the importance of measuring thixotropy and non-recovery rate R of non- Newtonian properties for realistic representation of the flow behaviours of solder paste.