- Provide a homogeneous suspension of the powder
- Prevent oxidation of the powder and surfaces
- Provide flow properties in printing
- Hold powder in place after printing
- Provide tack to hold components in position
- Provide self-alignment of components during reflow
- Inhibit re-oxidation of powder and surfaces to be joined during the reflow process
- Provide controlled cooling of the joint
- Insufficient solder paste
- Handling of the board (acceleration)
- Board support (preventing warpage)
- Tack force of the solder paste.
