Sliding speed effect in press-fit connection using Finite Element Analysis

Abstract

Solderless press-fit contacts in power module packages are now gaining more attention in the automotive industry especially in hybrid electric vehicles because of the Restriction of Hazardous Substances (RoHS) directive to eliminate lead-based connections. The production of press-fit assembly is also faster, more convenient, safer, and cheaper than soldered connections. In this paper, the effect of insertion speed of pin to the press-in force as well as the pull-out speed to the retention force was investigated using finite element analysis. An eye-of-the-needle (EON) shape compliant pin with general dimensions was adapted and a transient structural analysis in ANSYS mechanical was used to add and vary the speed of the press-fit pin geometry. Four simulations were conducted with different speeds. The results obtained by FEA show that the speed when kept at constant has no significant effect both on the press-in and retention force. However, when the speed changes due to acceleration, the press-in and pull-out force are both affected.