A Programmable System for Treatment of Alloy Steels at Cryogenic Temperatures
Treatment of alloy steels at cryogenic temperatures increases their wear resistance, which is an important consideration in industrial applications. The treatment of metal samples is performed in a dedicated cryogenic processor, with provisions for precise time/temperature control of the samples on the basis of pre-defined temperature protocols. There is little information on the design and construction of cryogenic processors in the open literature. In this paper, development of a simple and inexpensive programmable processor for treatment of metals at cryogenic temperatures has been presented. Considerations for the selection of suitable cooling method and reduction of liquid nitrogen consumption have been discussed. To demonstrate the usefulness of this processor, a metal sample has been cryotreated. Results of the treatment show a more uniform microstructure and less retained austenite in the treated metal sample, which is due to the transformation of most of austenite into the harder martensite phase. Overall results show that the design methodology presented in this paper can be adopted by other researchers for constructing similar processors for studying the effect of cryogenic temperatures on enhancement of wear resistance and other mechanical properties in metals.
M.S.J. Hashmi, S. Mridha and S. Naher
F. Farhani and K. S. Niaki, "A Programmable System for Treatment of Alloy Steels at Cryogenic Temperatures", Advanced Materials Research, Vols. 264-265, pp. 1240-1245, 2011