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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.

This paper attempts to compare and contrast cryogenic treated and untreated carbide cutting tool in turning operation of AISI304 steel. Machining parameters, namely cutting speed, feed rate and depth of cut are optimized for cryogenic treated tools. Tool life of the insert was determined based on the tests performed such as hardness, surface roughness and maximum wear. A design of experiments (DOE) and an analysis of variance (ANOVA) have been incorporated in the study. The objective of the paper is to determine the effects of each parameter on the surface roughness and tool wear. Material characterization was carried out using scanning electron microscope (SEM) and the maximum wear was estimated using optical microscope before and after the cryogenic treatment. The experimental results showed that cryogenic treated cutting tools significantly reduction in surface roughness, improves resistance to wear than untreated one. A confirmation test was performed between experimental and optimum values and the results are found to be in good agreement.

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.

Nanotechnology, the framework of the next industrial revolution has changed our vision, expectations and abilities to control the material world. The furtherance of Nanoengineering and Nanoscience lately has attracted the researchers to focus their attention on magnetic nanowires, such as Ferum, Cobalt, and Nickel. The distinctive characteristics of magnetic nanowires such as good conductivity, optical transparency, electrical and chemical inertness as compared to bulk materials have opened avenues for the evolution of novel devices like acoustic sensors, biomedicines, ultrahigh density data storage devices and recording media. To achieve this, nanomagnetic materials should be tailored to match the requirements for each kind of application. Among the variety of manufacturing processes that exist, electrodeposition is the most promising alternative method for enabling passage from laboratory to industry and is currently one of the most active lines of work in nanoscience. Within this framework, this paper summarises the latest researches and progress of Cobalt nanowire technologies and their applications in diversified industries, different synthesis conditions, methodologies and various characterisation techniques used to study and characterise the Cobalt nanowires produced to understand its attributes and behaviours.

The objective of this investigation is to explore the mechanical and wear characteristics of heat-treated hybrid metal matrix composites (MMCs) comprising Al6061, 5 wt.% graphite and different fractions of Titanium Carbide. In this, composites of different configurations were prepared by employing liquid metallurgy technique. The accumulation of graphite was kept constant that is 5 wt.% while TiC was varied from 0% to 8 wt.% in a stage of 2% and are subjected to T6 heat treatment. At first, composites were exposed to solutionising heat treatment at 530°C for 8 h and followed by quenching in ice and water. Artificial ageing of quenched composites was performed for an interval of 4-10 h in a step of 2 h. The role of heat treatment and ageing behaviour of composites on mechanical and wear characteristics were investigated and compared with un-heat treated. The result shows superior hardness and wear properties of MMCs for T6 heat treatment.