Ferritic stainless steels contain 16%–30% chromium and about 0.05%–0.25% carbon in their compositions. As the carbon and chromium content is high, precipitation of carbide particles provides high ...strength but also causes brittleness. Ferritic stainless steels are of moderate formability with an excellent corrosion resistance and relatively inexpensive. In this study, the predetermined JC model parameters of the AISI 430 ferritic steels have been verified by comparing the experimental drilling process and drilling simulations. Firstly, the drilling experiments of 430 steel with the uncoated tungsten carbide drill have been performed at three different feed rates and cutting speeds. Then, the pre-determined JC parameters have been adapted into a simulation software running with the finite element method and after the drilling simulations have been operated under the same drilling conditions. By comparing the experimental and numerical data based on the thrust force (Fz), a deviation of 4.83% has been calculated and the validity of the material's JC parameters has been demonstrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•This review article covers the application of smart manufacturing system.•Smart monitoring of hole machining has been discussed in details.•Various sensors, signal processing and other methods have ...been discussed.•It gives information about how important indirect measuring methods are in hole machining.
This review paper summarizes the application of smart manufacturing systems utilized in drilling and hole machining processes. In this perspective, prominent sensors such as vibration, cutting forces, temperature, current/power and sound used in the contemporary indirect and direct tool condition monitoring systems are handled one-by-one according to their applications during machining of holes. Thus, it is aimed to show several operations with the application stages and literature papers which utilize the sensorial data such as grinding, reaming, broaching, boring, tapping, drilling and countersinking. The novel side of this paper is summarizing the all-hole machining processes utilizing sensor systems while benefitting their predictive ability for improved machinability characteristics such as surface integrity, tool wear, dimensional accuracy, chip morphology.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cryogenic cooling has gathered significant attention in the manufacturing industry. There are inherent difficulties in machining materials that are difficult to machine because of high levels of ...hardness, abrasiveness, and heat conductivity. Increased tool wear, diminished surface finish, and reduced machining efficiency are the results of these problems, and traditional cooling solutions are insufficient to resolve them. The application of cryogenic cooling involves the use of extremely low temperatures, typically achieved by employing liquid nitrogen or other cryogenic fluids. This study reviews the current state of cryogenic cooling technology and its use in machining difficult-to-machine materials. In addition, this review encompasses a thorough examination of cryogenic cooling techniques, including their principles, mechanisms, and effects on machining performance. The recent literature was used to discuss difficult-to-machine materials and their machining properties. The role of cryogenic cooling in machining difficult materials was then discussed. Finally, the latest technologies and methods involved in cryogenic cooling condition were discussed in detail. The outcome demonstrated that the exploration of cryogenic cooling methods has gained prominence in the manufacturing industry due to their potential to address challenges associated with the machining of exotic alloys.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Although chip morphology changes according to the machining method and related cutting parameters, chip formation affects the quality of the machined surface. In this context, it is very important to ...understand the relationship between chip morphology and surface quality, especially in materials that are difficult to machine. In the presented study, the changes in chip morphology, surface morphology, and surface quality criteria (Ra and Rz) that occurred during the milling of precipitation-hardened steel in different cutting environments were analyzed. Milling experiments were carried out in dry, MQL (minimum quantity lubrication), nano-MQL (graphene), nano-MQL (hBN), Cryo, and Cryo-MQL environments using TiAlN-coated inserts and three different cutting speeds and feed rates. While the highest values in terms of Ra and Rz were measured in dry machining, the minimum values were obtained in a nano-MQL (hBN) cutting environment. Due to the lubrication and low friction provided by the MQL cutting environment, chips were formed in thinner segmented forms. This formation reduced the chip curve radius and thus provided a more stable surface morphology. On the other hand, Cryo-ambient gas could not effectively leak into the cutting zone due to the intermittent cutting process, but it increased the brittleness of the chips with the cooling effect and provided a similar surface morphology. The values of minimum Ra and Rz were obtained as 0.304 mm and 1.825 mm, respectively, at a 60 m/min cutting speed and 0.04 mm/rev feed. Consequently, the use of nano-MQL cutting medium is seriously recommended in terms of surface quality in milling operations of difficult-to-machine materials.
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The study presents the machinability of Nimonic 80A superalloys depending on the cutting forces in both the turning experiments and simulations by finite element method (FEM) in order ...to approve the precision of the predetermined Johnson-Cook (JC) parameters from our previous study. In the first part of the paper, the turning experiments have been performed on Nimonic 80A superalloy with coated carbide tools to determine the cutting forces namely main cutting force, feed force and radial force. Three different cutting parameters namely depth of cut, cutting speed and feed rate have been used with three levels. The effect levels of the cutting parameters on cutting forces have been also determined with the analysis of variance (ANOVA) at 95% confidence level. Secondly, predetermined JC material model parameters have been inputted into the software running by FEM. Thereafter, the turning simulations have been performed by FEM with the same cutting conditions as experimental ones. According to ANOVA results, depth of cut is the most important parameter on Fc and Ff while feed rate is the most important factor on the Fr. Through the closer results (the mean of 6.45% deviation) of cutting forces between the experiments and simulations, the JC parameters of the material and the boundary conditions of the simulations have been approved with high accuracy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The wide range of aluminium variants (alloys and composites) has made it an important material for aviation, automotive components, auto-transmission locomotive section units, S.C.U.B.A. tanks, ship, ...vessels, submarines fabrication and design etc. regardless of the fact that the aluminium alloys were being utilized in myriads of sectors owing to its exceptional superior and versatile functional characteristics, the property such as wear-resistant ought to be enhanced in order to further prolong diverse spectrum of applications. An aluminium alloy having lower hardness and tensile strength has been incorporated with silicon carbide that drastically strengthens the properties. This study involves fabrication of aluminium silicon carbide with muscovite/hydrated aluminium potassium silicate/aluminosilicate in stir casting method to obtain a hybrid metal matrix composite. Maintaining a constant amount of aluminium and silicon carbide, muscovite or hydrated aluminium potassium silicate is varied to obtain three distinctive compositions of (Al/SiC/muscovite) composites. The mechanical characteristics like tensile-strength, flexural-strength, toughness, hardness, scratch adhesion, percent-porosity and density were studied. The dispersion of muscovite and silicon carbide particles were observed by viewing the microstructure photographs obtained using optical microscopy and Scanning Electron Microscope (SEM). EDAX analysis affirms the presence of reinforcing constituents in Al–Mg–Si–T6 alloy matrix. A drum type wear apparatus was utilized to evaluate the percentage of wear-loss in different compositions using different loads and it was found that the wear-loss decreases linearly as the muscovite percentage was increased.
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•Machining of 2205 Duplex Stainless Steel under dry and different positions of MQL nozzles conditions was performed.•Influence of different nozzle spray mode i.e., rake face and flank face was ...studied.•The tribological and machining characteristics were analysed.•The mixed nozzle position i.e., on rake and flank face significantly improves the machining as well as tribological characteristics.
In this work, the sustainable machining approach is promoted by implementing the dry and minimum quantity lubrication (MQL) cooling conditions in the turning of duplex stainless steel. Initially, the turning experiments were performed under dry as well as MQL conditions and then, the influence of different positions of MQL nozzles on tribological and machining performance of 2205 duplex steel was investigated. The cutting parameters were kept fixed and the performance is evaluated in terms of surface roughness, micro-hardness, energy consumption, tool wear, machined surface microstructure and chips morphology. The results demonstrated that the highest average surface roughness values were obtained under dry conditions, with a value of 2.20 µm while MQL (flank + rake directions) produces the lowest surface roughness value of 1.55 µm with an improvement of 30%. Moreover, dual-jet MQL gives the lowest energy consumption (229 kJ) and tool wear (0.15 mm) with 23.67% and 52.38% enhancement, respectively.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
8.
An investigation on braking systems used in railway vehicles Günay, Mustafa; Korkmaz, Mehmet Erdi; Özmen, Ramazan
Engineering science and technology, an international journal,
April 2020, 2020-04-00, 2020-04-01, Volume:
23, Issue:
2
Journal Article
Peer reviewed
Open access
The high safety and comfort expectations under varying conditions have required the development of brake systems in railway vehicles. The main factors affecting the performance and function of the ...brake system are braking force, mass and speed of the vehicles, stopping or braking distance, railway condition and environmental factors. In this work, the brake systems such as disc and tread brakes, dynamic brakes, aerodynamic brakes, vacuum brakes, electro-pneumatic brakes have been reviewed. The braking systems are examined in two main groups as adhesion dependent and independent brakes. Evaluations have been made on brake disc-pad mechanisms which are the most important components in all brake systems in terms of safe operation especially for freight and high-speed trains. In this context, the experimental and numerical analysis studies on the interactions of brake system components including brake disk-pad geometries and material properties have been considered. Accordingly, research and development studies based on finite element modeling and prototype manufacturing is recommended in order to produce high efficiency and safety brake systems compatible with rail system vehicle. The information obtained from these studies will indirectly contribute to sustainability. Furthermore, this review study focused on the detailed analysis of scientific and applied research can contribute to the productivity of institutions and organizations operating in the braking systems of railway vehicles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Nanolubricants' role in friction reduction, wear resistance, and machining efficiency applications is studied.•Lubricants and their properties are revealed.•Nanoparticles types, their basic ...structure, and their different applications in machining and tribology are discussed.
Nanofluids are a unique class of fluids generally prepared by adding nanosized particles to different types of base fluids, such as water, oil, etc. When nanoparticles are added to the base fluids, their thermophysical parameters like viscosity, heat transfer characteristics, and thermal conductivity are improved and provide good results. For this reason, the demand for fluids enriched with nanoparticles has considerably increased in the manufacturing sector. This comprehensive state-of-the-art review covers nanolubricants' role in friction reduction, wear resistance, and machining efficiency applications. Initially, the lubricants and their properties are revealed in the introduction section. Then, the different types of nanoparticles, their basic structure, and their different applications in machining and tribology are portrayed in different sections. In addition, it provides a comprehensive analysis of the difficulties related to nanofluids and their utilization in machining and tribology. Ultimately, this evaluation provides final comments on the latest advancements in both the academic and industrial sectors, as well as a strategy for future expansion. The results indicated that the fluids loaded with nanoparticles had a beneficial effect in lowering friction and temperature at the primary contact zone.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Powder bed fusion based additive manufacturing techniques involve melting or sintering of powder particles via laser beams to join them in order to attain desired shapes. This study aims to provide ...basis for material constitutive parameters of widely used aluminum alloy AlSi10Mg alloy. Initially, tensile samples of AlSi10Mg alloy samples were manufactured by using SLM technology. Afterwards, through quasi-static and high temperature tensile tests, an attempt has been made to determine the Johnson–Cook material model of AlSi10Mg. in order to conduct quasi-static tensile tests, strain rates of 10−3 s−1, 10−2 s−1 and 5 × 10−2 s−1 were considered and tests were conducted at ambient temperature. Whereas, for high temperature tensile tests 24, 150, 300 °C temperature values were considered at the reference strain rate value of 10−3 s−1. The numerically simulated tensile results achieved by using the established Johnson–Cook model were then compared with experimental results. It was observed that the maximum error between the test and simulation results was around of 7.5%. The error percentage is well within the acceptable, thus proving the accuracy of the established material model.
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