This paper is a state-of-the-art review of the use of cryogenic cooling using liquefied gases in machining. The review is classified into two major categories namely, cryogenic processing and cryogenic machining. In cryogenic processing also known as cryo-processing the cutting tool material is subjected to cryogenic temperatures as a part of its heat treatment process. The majority of the repo...

This paper studied the cutting properties of Ti-6Al-4V under cryogenic cooling to find a solution of improvement in tool load-carrying, thermal stress, tool life and finish quality. Firstly, this paper established a 3-D cutting model of Ti-6Al-4V under cryogenic cooling with liquid nitrogen, and then set the parameters of material, friction model and cutting conditions. Based on this model, the...

Vibration free cooling of detectors to cryogenic temperatures is critical for many terrestrial, airborne, and space based instruments. Cooling of solids by anti Stokes fluorescence is an emerging refrigeration technology that is inherently vibration free and compact, and enables cooling of small loads to cryogenic temperatures. In this Highlight, advances in laser cooling of solids are discusse...

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Cryogenic treatment, like the freeze-thaw process, has been reported to be effective in modifying the physicochemical properties of polymeric hydrogels. However, not much attention has been paid to this process in terms of the precipitation of surfactant-water systems. In this study, two effective cryogenic methodologies were successfully reported to alter the physicochemical properties of a pr...

joule-thomson cooling systems are used in refrigeration processes such as cryogenic gas liquefaction. although extensive studies have been carried out by researchers, most of them include cryogenic heat exchangers and their associated fields. in the current study, an attempt was made to indicate the effect of using inappropriate operational conditions in a cryogenic joule-thomson cooling system...

We review the field of laser cooling of solids, focusing our attention on the recent advances in cryogenic cooling of an ytterbium-doped fluoride crystal (Yb:YLiF4). Recently, bulk cooling in this material to 155 K has been observed upon excitation near the lowest-energy (E4–E5) crystal-field resonance of Yb3+. Furthermore, local cooling in the same material to a minimum achievable temperature ...

Joule-Thomson cooling systems are used in refrigeration processes such as cryogenic gas liquefaction. Although extensive studies have been carried out by researchers, most of them include cryogenic heat exchangers and their associated fields. In the current study, an attempt was made to indicate the effect of using inappropriate operational conditions in a cryogenic Joule-Thomson cooling system...

NASA will need technology to cool detector systems to sub Kelvin temperatures for its future science program which includes missions such as the BLISS on SPICA, IXO, CMB-Pol, SPIRIT and SAFIR. Building on missions such as Spitzer, Planck, and ASTRO-E and the James Webb Space Telescope (JWST), new cooling technologies offer major advantages including long lifetimes, lower mass, and new capabilit...

heat exchangers are the critical components of refrigeration and liquefaction processes. selection of appropriate operational conditions for cryogenic recuperative heat exchanger and expansion valve operating in joule-thomson cooling system results in improving the performance and efficiency. in the current study, a straightforward procedure is introduced to design an efficient joule-thomson co...