Vibration Testing

HALT and HASS Testing

By combining temperature, temperature change, and multi-axis vibration, accelerated tests using high rate temperature vibration chambers can rapidly identify process defects and expose design weaknesses in a wide range of electronic products. Using well-defined acceleration factors developed at CALCE, highly accelerated life tests (HALT) provide assessments of lifetime and MTBF, reduce product development cycle time, and increase confidence in the product's life-cycle reliability.

The high-rate temperature vibration chamber is capable of temperature ranges of 150^oC to -100^oC at a temperature rate of change of 60^oC/minute (see below). Thermal cycling is achieved by convection heating and liquid nitrogen cooling. The chamber is also equipped with four pneumatic actuators capable of providing simultaneous repetitive shock vibration (RSV) stresses on fixtured test articles across a wide frequency range. The vibration controller is equipped with several time-domain, frequency-domain and fatigue analysis software tools. The spectral distribution of the RSV shaker is fixed by design but can be altered to a limited extent with suitable load train and fixture design.

Test setups involve the use of thermocouples to obtain the temperature distributions across the specimen, accelerometers and strain gages to capture deformation histories of the specimen. The number and strategic placement of vibration sensors is determined through preliminary modal analysis of the CCA. Transient event detectors are used for detecting and monitoring failures.