A CRYOGENIC TREATMENT APPARATUS WITH STEADILY DESCENDING RATE OF TEMPERATURE

作者：Chen Yong Chwang^*; Chen Han Ming

来源：Journal of the Chinese Institute of Engineers, 2010, 33(6): 909-914.

DOI：10.1080/02533839.2010.9671679

• cryogenic treatment
• subzero treatment
• thermal shock
• thermal stress

A buoyancy-driven apparatus, which is more efficient than the equipment currently used in cryogenic treatment, is designed in this experiment. Workpieces are slowly and steadily cooled down from room temperature to the temperature of liquid nitrogen in order to extend their service life. This process, over an appropriate time period, allows for the relaxation of internal stress and the stabilization of microstructures. Compared with the cryogenic equipment used in industries, the buoyancy-driven cryogenic apparatus designed in this study allows for lower temperatures to be reached and more effective treatment attained as the temperature descending rates are steadier and smoother, and there is an absence of abrupt temperature fluctuations. The buoyancy-driven apparatus is also cost effective as the consumption rate of liquid nitrogen is relatively low, which thus reduces the costs of cryogenic treatment.

• 出版日期2010-9