The Phenomenon Of Cold-pressed Needle Wires Being Pulled Out After Thermal Expansion And Contraction Cycles.

As an important form of solderless insertion technology, crimp contact female provides mechanical and electrical connections between conductors and circuit boards. However, under repeated high and low temperature cycles, due to differences in the thermal expansion coefficients of materials, the internal force field of the connecting components changes, potentially leading to conductor displacement or even pull-out. Thermal expansion and contraction cause the interference engagement state between the connecting hole and crimp contact male to be constantly adjusted during thermal cycles. The accumulation of these internal stresses may cause slight loosening or even peeling of the contact state between the pin and the hole wall.

Under thermal cycling conditions, the inherent residual stress and thermomechanical coupling in the connection zone have a significant impact on the stability of the crimp socket contact. The material expands at high temperatures and contracts at low temperatures. The inconsistent thermal expansion and contraction rates of different materials during this period will cause a redistribution of local interfacial stress, thereby changing the indentation relationship between female crimp contact and the hole wall. When the temperature changes repeatedly over a long period or the number of cycles exceeds a certain threshold, these changes may gradually weaken the mechanical engagement force between the connecting components, causing conductor displacement or even pull-out.