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The purpose of this paper is to present the comparison of sustainability characteristics of conventional and computer numerical control (CNC) turning process. The sustainability performance measures of both the processes were also being evaluated.

The study discusses the achievement of sustainability characteristics at the manufacturing process level of widely used industrial process, mechanical machining. Sustainable development includes improvements in material, product design and manufacturing process orientations. The present study narrates the sustainability characteristics at the process level.

The results confirm that the overall sustainability characteristics of CNC machining are potentially high considering the economic and environmental aspects of the machining parameters. A detailed life cycle analysis for both conventional and CNC turning was performed to evaluate the environmental impact and benefits.

The study contributed in the paper is limited to process dimension of sustainability. The economic and environmental aspects of machining were also being discussed.

The conduct of the study enabled the comparison of sustainability characteristics of conventional and CNC-turning processes. The approach could also be expanded for the comparison of sustainability characteristics of other manufacturing processes also.

The study is an attempt to explore the process sustainability by the comparison of environmental impact of making processes. Hence, the contributions are original.

The purpose of this work is to investigate the performance of non‐contaminating metal cutting environments and investigate the associated tool chip interface conditions. The work benchmarks flood coolant characteristics and considers gaseous cutting environments as possible alternatives.

Cutting trials were undertaken for a range of cutting environments. Flood coolant was investigated as was dry cutting, compressed air, room temperature nitrogen and liquid nitrogen environments. A range of cutting variables was measured in order to document the effect of cutting environment.

The gaseous component of the liquid nitrogen environment limited the adhesion on the tool face to a region along the flank edge of the tool, shifting rake face conditions from seizure to that of sliding. Tighter chip curl, shorter contact lengths, reduced adhesion and lower feed forces are evidence that liquid nitrogen is acting as a “liquid inert barrier” beneath the chip within the tool/chip interface.

Only one tool work combination has been investigated. More tool work combinations will need to be investigated.

The work demonstrated that it is possible to use environmentally safe environments during metal cutting operations. This reduces the exposure of the environment and machine tool operatives to compounds which have been shown to have detrimental effects on the environment and human health.

The work has led to presenting a hypothesis that liquid nitrogen acts as a “liquid inert barrier” beneath the chip within the tool/chip interface.

A researcher at Northwestern University's McCormick School of Engineering and Applied Science (Evanston, Illinois) has developed an X‐ray device that is believed to be the first practical means of detecting corrosion hidden beneath the surface of an aircraft's body. When the “virtual core drill” is positioned against the side of an aircraft, a computer screen shows an image of the layers of metal under the surface of the skin. If one or more of those layers are corroded, the amount of corrosion will be recorded on the screen, to an accuracy of 1/1.000 of an inch. The virtual core drill or, more technically, a Compton backscatter depth profilometer, was invented by Larry Lawson, research scientist at the McCormick School's Centre for Quality Engineering and Failure Prevention. The device sends con‐trolled X‐ray beams through the plane's body and detects those X‐rays that are deflected back at an angle near 90° from each layer. Today, whenever corrosion is detected on aircraft, the section must be dismantled, the layers pulled apart, and a micrometer used to measure the thickness. If the corrosion represents more than 10 per cent. the part must be replaced. The virtual core drill can eliminate the downtime and the damage that occurs when aircraft have to be torn apart for inspection. The new device includes a 200lb scan head, which is attached to the plane using feet shaped like suction cups while supported by a flexible boom mounted on a vehicle resembling a fork‐lift truck. The vehicle moves the scan head up and down the aircraft. The drill is equipped with the most sensitive detector known, the sodium iodide scintillator. The drill provides the same kind of information, layer by layer, as would be provided by cutting a plug out of the aircraft with a core drill, except that the aircraft is undamaged. Radiation exposure also is minimal.

TO say that the Twenty‐fourth S.B.A.C. Show was an unqualified success is perhaps to gild the lily. True there were disappointments— the delay which kept the TSR‐2 on the ground until well after the Show being one—but on the whole the British industry was well pleased with Farnborough week and if future sales could be related to the number of visitors then the order books would be full for many years to come. The total attendance at the Show was well over 400,000—this figure including just under 300,000 members of the public who paid to enter on the last three days of the Show. Those who argued in favour of allowing a two‐year interval between the 1962 Show and this one seem to be fully vindicated, for these attendance figures are an all‐time record. This augurs well for the future for it would appear that potential customers from overseas are still anxious to attend the Farnborough Show, while the public attendance figures indicate that Britain is still air‐minded to a very healthy degree. It is difficult to pick out any one feature or even one aircraft as being really outstanding at Farnborough, but certainly the range of rear‐engined civil jets (HS. 125, BAC One‐Eleven, Trident and VCIQ) served as a re‐minder that British aeronautical engineering prowess is without parallel, while the number of rotorcraft to be seen in the flying display empha‐sized the growing importance of the helicopter in both civil and military operations. As far as the value of Farnborough is concerned, it is certainly a most useful shop window for British aerospace products, and if few new orders are actually received at Farnborough, a very large number are announced— as our ’Orders and Contracts' column on page 332 bears witness. It is not possible to cover every exhibit displayed at the Farnborough Show but the following report describes a wide cross‐section beginning with the exhibits of the major airframe and engine companies.

As more stringent environmental legislation is enforced throughout Europe manufacturing businesses, employing metal cutting processes, can no longer ignore the growing importance of environmental aspects relating to cutting fluids. Businesses, through market forces, are being forced into offering a “clean solution” to the metal cutting processes which they operate. Cutting fluids despite playing an important role in metal cutting, have considerable environmental impact. There is a need therefore to understand the role of cutting fluids within the cutting process in order to evaluate possible environmentally friendly alternatives to the use of cutting fluids. In order to achieve this the operating environment in which the process is being carried out, and the consequences of removing the cutting fluid from the process altogether has to be assessed. This paper therefore, reflects on the role of cutting fluid and the implications of their use. Viable methods of reducing cutting fluid consumption are also reported, together with efficient methods of cutting fluid utilisation (e.g. minimum quantity delivery systems). Finally, the difficulties experienced in removing cutting fluids from the metal cutting process are highlighted through the consideration of dry cutting technologies.

NO document issued by the National Board for Prices and Incomes is of more importance to people engaged in work study than Report 83 on Job Evaluation. It lists nine definitions by various authorities but contents itself with a fairly simple one; the comparison of jobs by the use of formal and systematic procedures, set down on paper and adhered to as distinct from rule of thumb methods, with subsequent analysis determining the relative positions of jobs in a wage structure.

The purpose of this paper is to compare the performance of single- and dual-channel minimum quantity lubrication (MQL) for reaming spool bores in an automotive transmission valve body.

Machining experiments are conducted under various parameters for both single- and dual-channel MQL. Comparison metrics include part surface temperature, spindle power consumption and hole quality. Experimental data from traditional through-tool flood coolant are provided as a baseline for spindle power consumption and part quality.

The results show that with proper tooling and machining parameters, dual-channel MQL can perform equivalently or better than flood coolant. Single-channel MQL was not deemed suitable for this machining application.

The results of the study show that MQL can be successfully applied for precision reaming of aluminum and can provide guidance in developing an MQL system.

Few studies have been performed for reaming holes in general, and very few studies have been performed for reaming with MQL. Reaming is a critical operation used to create holes with precise quality. No study was found in the literature review that directly compared the performance of single- and dual-channel MQL delivery systems.

This paper aims to examine the performance of the machining parameters used in the hard-turning process of DIN 1.2738 mold steel and identify the optimum machining conditions.

Experiments were carried out via the Taguchi L18 orthogonal array. The evaluation of the experimental results was based on the signal/noise ratio. The effect levels of the control factors on the surface roughness and flank wear were specified with analysis of variance performed. Two different multiple regression analyses (linear and quadratic) were conducted for the experimental results. A higher correlation coefficient (R²) was obtained with the quadratic regression model, which showed values of 0.97 and 0.95 for Ra and Vb, respectively.

The experimental results indicated that generally better results were obtained with the TiAlN-coated tools, in respect to both surface roughness and flank wear. The Taguchi analysis found the optimum results for surface roughness to be with the cutting tools of coated carbide using physical vapor deposition (PVD), a cutting speed of 160 m/min and a feed rate of 0.1 mm/rev, and for flank wear, with cutting tools of coated carbide using PVD, a cutting speed of 80 m/min and a feed rate of 0.1 mm/rev. The results of calculations and confirmation tests for Ra were 0.595 and 0.570 µm, respectively, and for the Vb, 0.0244 and 0.0256 mm, respectively. Developed quadratic regression models demonstrated a very good relationship.

Optimal parameters for both Ra and Vb were obtained with the TiAlN-coated tool using PVD. Finally, confirmation tests were performed and showed that the optimization had been successfully implemented.

Inconel 718 is difficult to machine due to its high toughness and study hardenability. Though the use of cutting fluids alleviates the problem, it is not sustainable. So, supply of a small quantity of specialized coolant to the machining zone or use of a solid lubricant is a possible solution. The purpose of the present work is to improve machinability of Inconel718 using graphene nanoplatelets.

In the present study, graphene is used in the machining of Inconel 718 alloy. Graphene is applied in the following two forms: as a solid lubricant and as an inclusion in cutting fluid. Graphene-based self-lubricating tool and graphene added nanofluids are prepared and applied to turning of Inconel 718 at varying cutting velocities. Performances are compared by measuring cutting forces, cutting temperature, tool wear and surface roughness.

Graphene, in both forms, showed superior performance compared to dry machining. In total, 0.3 Wt.% graphene added nanofluids showed the lowest cutting tool temperature and flank wear with 44.95% and 83.37% decrease, respectively, compared to dry machining and lowest surface roughness, 0.424 times compared to dry machining at 87 m/min.

Graphene could improve the machinability of Inconel 718 when used in tools as a solid lubricant and also when used as a dispersant in cutting fluid. Graphene used as a dispersant in cutting fluid is found to be more effective.