Destructive Evaluation
Mechanical destructive testing evaluates the adhesion strength and fracture behavior of surface-mount solder connections under lateral loading conditions. The protocol known as component shear testing measures the peak force required to detach a device from its printed circuit board pad. It establishes a baseline of mechanical integrity for solder joints across different board finishes.
Test Methodology
Execution of this physical test involves a motorized shear tool that applies a lateral force at a controlled height above the printed circuit board surface. The test equipment monitors the load continuously until the solder joint fractures, registering the maximum force as the shear strength. A low tip height must be maintained to prevent the component from tipping or lifting, which would introduce unwanted bending moments into the measurement.
Analyzing the fractured surface helps to identify whether the failure occurred within the solder alloy or at the intermetallic interface.
Quality Control
Manufacturing facilities use these shear force values to monitor the quality of the reflow process and the cleanliness of component pads. This quantitative metric provides immediate feedback on the consistency of the printing, placement, and reflow steps. Low shear strength values often signal insufficient intermetallic compound growth or bad solder wetting.
