Proceedings Article | 8 January 2008
Proc. SPIE. 6835, Infrared Materials, Devices, and Applications
KEYWORDS: Infrared detectors, Contamination, Reliability, Finite element methods, Infrared radiation, Analytical research, Helium, Failure analysis, Cryocoolers, Cryogenics
With extensive application of infrared detective techniques, Stirling cryocoolers, used as an active cooling source, have
been developed vigorously in China. An overview of the status and performance for some Stirling cryocoolers having
been developed is presented. To analyze the cooler's reliability characteristic, failure analysis has been done, and the
four crucial failure modes affecting cooler's long-life running are wear, gaseous contamination, Helium leakage and
fatigue. According to each failure mechanism, the measures taken to control or minimize its damage were discussed, and
some experiments were designed and carried to quantitatively analyze the relationship between failure and performance
in detail. To the wear, an ageing test, which was thermal cycle and for about 500 h, was used to improve the internal
frication status and eliminate the defective products. To the gaseous contamination, an accelerated experiment was
carried by adding contaminants to the cooler by a 3-way valve to get the relationship between performance degradation
and amount of contaminants. The chance of a fatigue related failure is very small now because of the FEM analysis and
screening test. Based on charge pressure experiment results, the criteria to judge the sealing procedure was given by the
ratio of leak rate to cooler volume.
