The Performance Degradation Mechanism Of Piercing Clamps: How Thermal Cycling And Stress Affect The Stability Of Electrical Connections

In the daily operation of the power system, electrical piercing connector often faces harsh environmental challenges. Many engineers have found that initially tight connections loosen after several years of operation. The underlying physical logic behind this phenomenon lies in the silent "performance marathon" that the contacts undergo under complex operating conditions.

Fluctuations in physical properties caused by thermal cycling

The alternation of power load between day and night causes the cable temperature to fluctuate continuously. This repeated heating and cooling process challenges the metal and insulation materials inside the insulation connector clamp. Differences in the coefficients of thermal expansion between different materials lead to continuous microscopic compression and stretching.

Prolonged exposure to this temperature fluctuation environment causes subtle displacements in the internal crystal structure of the material. This fatigue, accumulated due to thermal expansion and contraction, gradually weakens the component's ability to maintain constant pressure.

The effect of sustained stress on material modulus

Mechanical fastening pressure is the basis for maintaining low-resistance contact. However, under constant or alternating stress, the internal structure of metallic materials undergoes slow evolution.

When this pressure is superimposed on the aforementioned thermal cycling effects, the weakening of physical properties becomes increasingly pronounced. insulation piercing will experience a decrease in elastic modulus under long-term thermal cycling and stress. This means the material becomes less "elastic" than in its initial state, and its resistance to deformation decreases.

The chain reaction following elastic modulus decrease:

Once the elastic modulus decreases, the contact force that was previously maintained by the material's elastic deformation also decreases. For insulation piercing clamp, this change is usually accompanied by an increase in contact resistance.

Although this subtle change in modulus is difficult to detect initially, the risk of micro-arc oxidation and interface aging increases over time. This structural weakening caused by changes in intermolecular forces is a core factor affecting long-term service life.