Abstract: Taking the inmold micro assembly molding of polymer micro mechanical motion pair as a research object, the effects and mechanisms of secondary molding process parameters and micro axial constraint on the thermalfluidstructure coupling deformation of preformed micro shaft induced by the secondary molding melt filling flow were investigated extensively. The resulted indicated that the thermalfluidstructure coupling deformation of preformed micro shaft induced by the secondary molding melt filling flow exhibited an increase with an improvement in secondary molding melt injection temperature, but a decrease with an increase of the constraining degree of two end for the preformed micro shaft in the secondary molding die. The reduction of secondary molding melt injection temperature or the increase of the constraining degree of the preformed micro shaft in the secondary molding die is favorable to the decrease of thermalfluidstructure coupling deformation of preformed micro shaft induced by the secondary molding melt filling flow. This can improve the inmold micro assembly forming precision of polymer micro mechanical motion pair.

Key words: in-mold micro assembly molding, thermal-fluid-structure coupling, micromachines, mechanism, deformation