In Circuit Fixture Spring Probe Force Balancing on Ultra Fine Pitch Assemblies
Balancing micro-probe forces with precision push-fingers prevents substrate strain over 500 microstrain, protecting fine-pitch BGAs and MLCCs from fixture damage.
Beryllium Copper
Material Composition
High-performance metal alloy provides the electrical conductivity and mechanical spring force required for battery contacts or test probes. Use of beryllium copper allows designers to create small, resilient connectors that maintain contact pressure over thousands of cycles. The material consists of copper with a small percentage of beryllium to increase tensile strength and hardness.
This alloy provides a balance between electrical conductivity and physical durability.
Elastic Recovery
Spring performance determines how well a contact returns to its original shape after being compressed. Beryllium copper is selected for its high fatigue strength, which allows it to endure repeated mechanical cycling without permanent deformation. Heat treatment processes are used to harden the alloy after it has been formed into the desired contact shape.
If the metal is not properly aged, the contact pressure will drop over time and lead to intermittent electrical connections. Engineers specify particular tempers of the alloy to match the deflection requirements of the connector housing.
Contact Reliability
Surface finishing protects the base metal from oxidation and ensures low contact resistance. Most beryllium copper components are plated with gold or nickel to maintain a clean interface for signal transmission. The alloy remains stable at elevated temperatures found in automotive and industrial environments.
This material is a standard choice for high-reliability interconnects in harsh conditions.