In the production of critical parts for various machines and mechanisms, expensive structural steels are used alloyed with chromium, nickel, molybdenum, vanadium. practice, wear resistance parts, especially under severe operating conditions, may be insufficient due to uneven microstructure content retained austenite. Therefore, increasing operational stability products made alloy is an importan...

The application of liquid nitrogen injection is an important technique in the field of coal mine fire prevention. However, the mechanism of heat and mass transfer of cryogenic nitrogen in the goaf porous medium has not been well accessed. Hence, the implementation of fire prevention engineering of liquid nitrogen roughly relied on an empirical view. According to the research gap in this respect...

Heat exchangers are the most important equipment in refrigeration processes. Design and modeling of heat exchangers operating at low temperatures are different from other regular heat exchangers. This study includes two sections. In the first section, design and modeling considerations needed for evaluating the real thermal behavior of heat exchangers at low temperatures were discussed. The...

A compact, two-stage R-404A / R-508b cascade refrigeration system designed for interface with a high-performance microprocessor is under development. Such a system, designed to remove 100 W at –70 °C, can avoid the high cost of deep cryogenic cooling. Because thermal interface design is critical in maintaining low chip temperatures, a compact, microchannel evaporator is used. A chemically micro...

As a supplemental process of heat treatment, deep cryogenic treatment (DCT) is believed to have favorable effects on the mechanical properties steels. In this study, three different sequences DCT and tempering, including QCTT (Q: quenching, C: DCT, T: tempering), QTC, QTCT, were investigated discover an effective method improve impact toughness fatigue life typical ultrahigh strength steel simu...

The effect of deep cryogenic treatment (DCT) on the artificial ageing kinetics a SiC particles reinforced aluminum alloy composite (SiCp-Al) is experimentally studied in this paper. evolutions both macro-properties (i.e., yield strength and ultimate tensile strength) microstructures (precipitates) have been investigated by set hardness tests, microstructural observations (scanning electron micr...