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The cutting tool in the machining process plays an important role as it acts on the working material. There are a few methodologies have been persued to improve tool life, for example traditional cooling, single layer coating, multilayer coating, heat treatment process, nitrogen cooling and latest being the cryogenic treatment which reported a significant improvement in cutting tool life, chip morphology, reduction in heat generation. Hence, the cryogenic treatment is emerged as the sustainable machining process.  This paper presents machining of AISI 304 steel using both cryogenic treated (CT) and untreated (UT) cutting tool insert. The commercially available uncoated carbide insert has been cryogenically treated at -196°C for 24 hours soaking period. The machining test has been  conducted under four different cutting speeds. The material characterization of cutting insert is studied by using scanning electron microscopy (SEM), hardness test, and microscopic image analysis has been carried out before and after cryogenic treatment. The cutting tool performance is assessed in terms of of wear, cutting temperature, chip morphology, surface roughness under the influence of cryogenic machining and the results are contrast with UT one. The exploratory findings reveals that the deep cryogenic treatment (DCT) with 24 hours soaking period, performed better wear resistance and improved surface roughness of the cutting tool. Also considerable reduction in the flank wear, crater wear, cutting temperature is obtained and found improved chip morphology.

LEDs, of late, have received attention as the next generation lighting system for enhanced luminous efficiency and higher lifespan. However, the thermal management of the LEDs is the crucial parameter to be countered for global acceptance as a revolutionary illumination source. This paper reports the experimental investigation of natural convective heat transfer of high power LED COBs using MWCNT and MWCNT-CuO nanofluids mixed with de-ionized water. The study uses MWCNT based nanofluids as a route to enhance the heat transfer of high power LEDs by the passive cooling technique. This study presents an innovative cooling device integrated with numerous fluid pockets, called the HSFP, to achieve the enhanced thermal performance of heat sinks for applications in high intensity LED lights. Nanofluids of various concentrations were formulated and their heat transfer performance evaluated using a series of experiments and compared with liquid cooling and a conventional heat sink. The experimental finding reveals 20-30% lowered thermal resistance using the new HSFP (nanofluids). Thus, the HSFP found to effectively dissipates the heat in high-power LED COBs using nanofluids as the cooling medium compared to the conventional heat sink.

The cutting tool in the manufacturing industry is a key factor. The fulfilment of machining operation mainly depends on the tool material to improve the cutting life of the tool during machining with austenite stainless steel, however the austenite stainless steel difficult to machine and less amount of heat dissipation during machining in order to overcome. The aim of the investigation is to apply; the cryogenic treatment (CT) to the tungsten carbide insert, besides no study has been claimed on the chip thickness (tc), tool wear of machining with AISI 304. The machining test was conducted by three different speed and unchanged feed rate and depth of cut. The maximum flank wear was measured by using digital microscope also measured the chip thickness for both insert. The experimental results found that to reach the maximum flank wear for CT insert in all three speed was less in comparison with untreated insert (UT), chip thickness was also less in case of CT insert, built up edge were clearly observed in the UT insert, over all CT insert performed more desirable in compared with UT. The improvement in the microstructure properties of the CT insert owing to development of Eta (η) phase carbide and homogenous distribution in the tungsten carbide material, SEM and XRD tests are confirmed these results

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