Nadig, DS and Ramakrishnan, V and Sampathkumaran, P and Prashanth, CS (2012) Effect of cryogenic treatment on thermal conductivity properties of copper. In: A1DVANCES IN CRYOGENIC ENGINEERING: Transactions of the International Cryogenic Materials Conference - ICMC, , 13–17 June 2011, Spokane, Washington, USA, pp. 133-139.
AIP_Conf_proc_1435_133_2012.pdf.pdf - Published Version
Copper exhibits high thermal conductivity properties and hence it is extensively used in cryogenic applications like cold fingers, heat exchangers, etc. During the realization of such components, copper undergoes various machining operations from the raw material stage to the final component. During these machining processes, stresses are induced within the metal resulting in internal stresses, strains and dislocations. These effects build up resistance paths for the heat carriers which transfer heat from one location to the other. This in turn, results in reduction of thermal conductivity of the conducting metal and as a result the developed component will not perform as per expectations. In the process of cryogenic treatment, the metal samples are exposed to cryogenic temperature for extended duration of time for 24 hours and later tempered. During this process, the internal stresses and strains are reduced with refinement of the atomic structure. These effects are expected to favourably improve thermal conductivity properties of the metal. In this experimental work, OFHC copper samples were cryotreated for 24 hours at 98 K and part of them were tempered at 423K for one hour. Significant enhancement of thermal conductivity values were observed after cryotreating and tempering the copper samples.
|Item Type:||Conference Proceedings|
|Additional Information:||Copyright for this article belongs to the American Institute of Physics.|
|Keywords:||Cryogenic treatment;Thermal conductivity;Residual stress;OFHC copper|
|Department/Centre:||Division of Physical & Mathematical Sciences > Centre for Cryogenic Technology|
|Depositing User:||Francis Jayakanth|
|Date Deposited:||03 Dec 2012 11:06|
|Last Modified:||03 Dec 2012 11:06|
Actions (login required)