Temperature Cycle Testing
During temperature cycle testing, mismatch of thermal coefficients of expansion of materials used in electronic and optoelectronic components are among the leading contributors to the failure of equipment exposed to extreme temperature variations. Repeated exposure to cyclic temperature variations (-70 to 200°C) can fatigue joints of different materials and cause them to fail. Conducting the temperature cycling test (air-to-air) on these components will assist in determining
1) the existence of thermal coefficient mismatch and
2) the sensitivity of these mismatches to repeated temperature excursions.
Along with temperature extremes, the temp cycle test is performed in chambers that control number of cycles, dwell times, transfer times, or ramp rates. Elevator-type chambers are used when ramp rates between the low temperature and high temperature extremes must occur at a fairly rapid rate (for MIL-STD-883, test method 1010, for example). If a slower ramp rate between temperature extremes is required, a temperature cycle test chamber with a single chamber is best suited. By using a single-chamber piece of equipment the chamber can be set for a specified, slower ramp (for example, 10°C per minute).
Powered Temperature Cycle is temperature cycling testing which includes operationally electrically biasing devices under the conditions of -65 to 150°C.
Powered Temperature Cycle Test Specifications / Standards
MIL-STD-883 Rev A-H,J, Method 1007
Temperature Cycle Test Specifications / Standards
MIL-STD-750 Rev A-F, Methods 1051 and 1055
MIL-STD-883 Rev A-H,J, Method 1010