In the current study, analysis, modeling, and optimization of machining with nano-additives based minimum quantity lubrication (MQL) during turning Inconel 718 are presented and discussed. ...Multi-walled carbon nanotubes (MWCNTs) and aluminum oxide (Al2O3) gamma nanoparticles were utilized as used nano-additives. The studied design variables include cutting speed, feed rate, and nano-additives percentage (wt. %). Three machining outputs were considered namely: flank wear, surface roughness, and energy consumption. The novelty here focuses on improving the MQL heat capacity by employing two different nano-fluids. The analysis of variance (ANOVA) technique was employed to investigate the influence of the design variables on the studied machining outputs. The results demonstrated that the usage of MQL-nanofluids improved the cutting process performance compared to the classical approach of MQL. It was found that 4 wt. % of added MWCNTs decreased the flank wear by 45.6% compared to the pure MQL. Similarly, it was found that 4 wt. % of added Al2O3 nanoparticles improved the tool wear by 37.2%. Besides, the nanotubes additives showed more improvements than Al2O3 nanoparticles in terms of tool wear, surface quality, and energy consumption. Regarding the modeling stage, artificial neural network (ANN), adaptive neuro-fuzzy inference system (ANFIS), and genetic programming (GP) are employed to model the measured outputs in terms of the studied parameters. These soft computing approaches provide various advantages through their self-learning capabilities, fuzzy principles, and evolutionary computational concept. In addition, a comparison among the developed models has been conducted to select the most accurate approach to present the machining characteristics. Finally, the non-dominated sorting genetic algorithm (NSGA-II) was utilized to optimize the studied cutting processes. Moreover, a comparison between the optimized results from different approaches is presented. The proposed methodology presented in this work can be further implemented in other machining cases to model, analyze as well as optimize the machining performance, especially for the hard-to-cut materials which are commonly used in different industries.
•Analysis and modeling of turning Inconel 718 with MQL-nano-fluids are proposed.•ANN, ANFIS, and GP were employed to model the studied outputs.•NSGA-II was utilized to optimize the studied cutting processes.•A clear mechanism of using MQL-nanofluid was offered.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, tool wear, surface integrity and chip formation are studied under both dry and wet cutting conditions. The turning results showed that the influence of coolant on tool life was more ...pronounced at higher cutting speeds than at lower cutting speeds. This is mainly because of the dominance of the mechanical wear mechanisms at lower cutting speeds and the lack of formation of a lubricating layer/film that can reduce the friction between the abrasive particle and the cutting tool. When turning at higher speeds, under wet conditions, the tool life was increased. However, the surface quality was deteriorated. This was mainly due to the flushing away of the partially debonded particulates from the machined surface, thus, forming higher percentage of pit holes and voids. The formation of chips with serrated edge was more pronounced during wet cutting, as a result of high thermal gradient. The microhardness measurements on the aluminium matrix beneath the machined layer showed higher values when cutting under wet conditions.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
An investigation is reported on the importance of integrating sustainability with manufacturing and design, along with other objectives such as function, competitiveness, profitability and ...productivity. The need of utilizing appropriate tools like design for environment, life cycle assessment and other environmentally sound practices that are cognizant of the entire life cycle of a process or product is highlighted. It is likely that sustainability and environmental stewardship will be increasingly important considerations in manufacturing and design in the future and are likely to influence the main priorities for advancing manufacturing operations and technologies. Designers and manufacturing decision makers who adopt a sustainability focus and establish a sustainability culture within companies are more likely to be successful in enhancing design and manufacturing. It is concluded that more extensive research and collaboration is needed to improve understanding of sustainability in manufacturing and design, and to enhance technology transfer and applications of sustainability.
This paper investigates the effect of cutting parameters and particulate properties (volume fraction and average particulate size) on the microhardness variations of the aluminium matrix beneath the ...machined surface. Orthogonal cutting tests were carried out on different aluminium matrix composites reinforced with varying volume fractions and average sizes of alumina particulates. Characterization of the machined subsurface was made using optical, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The metallographic analysis revealed severely damaged machined subsurface with numerous geometrical defects and plastically deformed aluminium matrix. This study also yielded some interesting findings on the influence of particulate volume fraction and average size in altering the microhardness in the aluminium matrix. The lower the reinforcement volume fraction and the coarser the particulates, the higher are the variations in matrix microhardness. The microhardness measurements on the aluminium matrix beneath the machined layer showed higher values when machining under wet conditions with reduced depth of plastically deformed zone.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper presents the development, implementation and application of a methodology to predict and control the surface quality of the additive manufacturing products based on an accurate ...representation of the cusps’ geometric model. A non-uniform rational B-spline (NURBS) model representing the geometry of cusps generated by layer-based manufacturing is employed, and its parameters are extracted by running experimental study of the fabricated test specimens. The significant difference of the results obtained using the developed models with what is used in common practice is discussed and demonstrated. Using the developed model, a unified solution to estimate the surface roughness based on the local surface gradient on the part and the selected fabrication layer thickness is presented. The results show that the developed methodology effectively estimates the local surface roughness of the fabricated products.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this paper, an attempt is made to evaluate the self-propelled rotary carbide tool performance during machining hardened steel. Although several models were developed and used to evaluate the tool ...wear in conventional tools, there were no attempts in open literature for modeling the progress of tool wear when using the self-propelled rotary tools. Flank wear model for self-propelled rotary cutting tools is developed based on the work-tool geometric interaction and the empirical function. A set of cutting tests were carried out on the AISI 4340 steel with hardness of 54–56 HRC under different cutting speeds and feeds. The progress of tool wear was recorded under different interval of time. A genetic algorithm was developed to identify the constants in the proposed model. The comparison of measured and predicted flank wear showed that the developed model is capable of predicting the rate of rotary tool flank wear progression.
► Assessment of the machinability of self-propelled rotary tool. ► State of the art review on self-propelled rotary tools and proposing a model to predict the tool wear. ► Present a simple geometrical based model to predict the progress of tool wear. ► Experimental study is performed to measure the progress of tool wear under wide range of process parameters. ► Measured data was used to verify the proposed model.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This paper presents an analytical force model to predict the forces generated during machining of metal matrix composites and investigates the effect of particle size on machining forces. Several ...aspects of the cutting mechanics such as shear force, ploughing force, and particle fracture force are considered to estimate the generated cutting forces. Chip formation force is obtained using the Johnson–Cook constitutive model. The ploughing force is formulated using the slip-line field theory, while the fracture force is calculated using Griffith Theory. The predicted results are compared to experimentally measured data under different conditions. The results show acceptable agreement between the theoretically predicted and experimentally measured cutting forces.
► Comprehensive analysis of all deformation mechanism encountered during cutting MMC. ► The analyses include the two and three body abrasion along the chip tool interface. ► Experimental verification of the presented work.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Austempered ductile iron alloys (ADI) are an interesting class of materials because of their unique microstructure and mechanical properties. When subjected to austempering treatment, ductile iron ...transforms to a microstructure consisting of ferrite and stabilized austenite rather than ferrite and carbide as in austempered steels. Because of the presence of stabilized austenite, austempered ductile iron (ADI) exhibits an excellent combination of strength and ductility together with good fatigue and wear properties. Accordingly, there is a growing interest in using ADI in several applications due to its mechanical properties. However, as with difficult-to-cut materials, the machinability rating of ADI is low and there is still a need to understand the impact of the cutting process parameters. Machinability of a material depends not only on its properties and microstructure, but also on the proper selection and control of process variables. The current work is focused on performing a machinability analysis of ADI in order to understand the effect of the cutting process parameters on the machined surface quality and tool life. It also studies the effect of different coolant strategies. Thus, the motivation of this study is to develop a better understanding of the influence of cutting parameters and cooling strategy to be able to machine ADI directly with acceptable tool life and cycle time. The design of experiments technique and response surface methodology is employed to analyze and model the measured responses. In addition, the cutting tool wear mechanisms are identified and discussed.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
5-fluorouracil (5-FU) is an antimetabolic agent used for treating slowly growing solid tumors like breast and ovarian carcinoma. Thymoquinone (TQ) is the main biologically active constituent of
, it ...has been found to demonstrate anticancerous effects in several preclinical studies, and this is because TQ possesses multitarget nature. Stem cells-derived exosomes are in the spotlight of research and are promising tissue regenerative and anticancer cell-derived nanovesicles.
Herein, we studied the antineoplastic effects of Exosomes derived from mammary stem cells (MaSCs-Exo) on breast cancer cells, alone or combined with TQ when compared to a breast cancer chemotherapeutic agent; 5-FU.
Our approach included performing viability test and measuring the expression of pro-apoptotic gene (Bax), anti-apoptotic gene (BCL-2) and angiogenic gene (VEGF) on Human MCF-7 cells (breast adenocarcinoma cells), the MCF-7 cells were cultured and incubated with medium containing 5-FU (25 μg/ml), TQ (200 μg/ml), MaSCs-Exo (100 μg protein equivalent), a combination of TQ (200 μg/ml) and MaSCs-Exo (100 μg).
Our obtained results show that TQ and MaSCs-Exo each can effectively inhibit breast cancer cell line (MCF-7) proliferation and growth. Also, the results show that the combination of TQ and MaSCs-Exo had higher cytotoxic effects on MCF-7 breast cancer cells than TQ or 5-FU, alone.
The present study shows a promising anticancer potential of exosomes isolated from mammary stem cells; this effect was potentiated by adding TQ with MaSCs-derived exosomes.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Proposing nano-cutting fluids contributes to facing the heat dissipation challenge during machining difficult-to-cut materials since they offer a highly observed thermal conductivity value in ...comparison with the base lubricants. Thus, several nano-additives are employed to improve the cooling efficiency of Minimum Quantity Lubrication (MQL) system since its heat capacity is much lower than the one achieved using flood coolant. MQL-nano-fluid technique offers two main advantages; (a) enhancing the machining process performance as the employed nano-additives improve the thermal and frictional behavior, and (b) accomplishing a more sustainable process as the MQL systems applies an optimal amount of oil compared to the flood coolant strategy. In this study, a previous general assessment algorithm has been implemented to find the optimal and sustainable process parameters levels during machining Inconel 718 with MQL-nano-fluids. Multi-walled-carbon-nano-tubes (MWCNTs) and aluminum oxide (Al2O3) gamma nanoparticles have been utilized as nano-additives. The employed algorithm accommodates several machining responses, and sustainable metrics and indicators regardless of their criteria. It has been found that the assessment algorithm results were in agreement with the physical findings of the conducted experimental results.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PDF
