Cutting performance and wear characteristics of PVD coated and uncoated carbide tools in face milling Inconel 718 aerospace alloy

In this paper, cutting performance and failure characteristics of two PVD TiN coated and an uncoated tungsten carbide grades with identical geometry are presented. Face-milling tests of Inconel 718 superalloy were performed to investigate the effect of cutting speed and feed rate on tools performance under wet conditions. Tools were thoroughly examined under SEM at two stages in order to reveal the failure modes and wear mechanisms. These stages were after cutting for 5 s and when the tool failed. It was noted that the coating resulted in a marginal improvement, as it was delaminated by adhering workpiece material at the beginning of the cut, impeding the performance of the tool for the rest of the experiment. A combination of progressive chipping and flank wear was the general mode of tool failure, former being dominant at high speeds and the latter at the low speed region. Results showed that uncoated tool performed better than coated tools at low cutting speeds while coated tools gave slightly better performance as the speed was raised

Machining performance of vegetable oil with phosphonium- and ammonium-based ionic liquids via MQL technique

Thermo-mechanical loads are the main factor that influences the tool wear and product surfaces during machining processes. Lubrication in metal cutting is an effective medium to reduce frictional forces and wear on the tool-workpiece interfaces. On this regards, the advantages of using refined bio-based metalworking fluids (MWFs) with the presence of low toxic, biocompatible and oil-miscible ionic liquids (ILs) additives ([N1,8,8,8][NTf2] (AIL) & [P6,6,6,14][(iC8)2PO2] (PIL)) at nominal weight concentrations of 1, 5 and 10% are explored during orthogonal cutting of AISI 1045 steel. Accordingly, the lubricants are supplied via minimum quantity lubrication (MQL) technique and comparative studies are conducted against the performance of the neat modified Jatropha-based lubricant (MJO) and commercially available synthetic ester-based MQL cutting fluid (SE). The combination of mist supply of the MJOs during machining have a great impact on cleaner production that eliminates the excessive usage of fluids and supports the utilization of environmentally friendly chemicals. This work extends the application of a minute quantity of fully miscible ILs in polar vegetable-based MWF which proven to provide a significant improvement on the lubrication effect of the MJO. MJOþAIL10% and MJOþPIL1% showed the best cutting performance amongst all lubricant mixtures with reduction of cutting forces and specific cutting energy by 4 to 5%, cutting temperatures by 7 to 10%, friction coefficient by 2 to 3%, tool-chip contact length by 8 to 11%, chip thickness by 22 to 25%, friction angle by 1 to 2% and increased shear angle by 25 to 29% compared to the SE. Besides, the effect of low friction and reduced cutting forces produced lower specific cutting energy that promotes “greener” and more sustainable working environment

Quality assurance of remanufactured components of end-of-life vehicle: a literature review

This objective of this work is to investigate the quality assurance of remanufactured ELV components by distinguished with other sustainable manufacturing stakeholders, 6Rs. The study is focused on developing countries such as China, India, Malaysia, and Brazil as the authors determine whether remanufactured ELV components are significant to the respective countries. Implications of this study are the three remanufacturing research areas classified and discussed: Remanufacturing Process, Remanufacturing Supply Chain, and Sustainable Remanufacturing Industry. The most significant findings in this study classified quality of remanufactured ELV components in terms of quality assurance and quality after business

Optimum performance of green machining on thin walled Ti6AL4V using RSM and ANN in terms of cutting force and surface roughness

Thin walled titanium alloys are mostly applied in the aerospace industry owing to their favorable characteristic such as high strength-to-weight ratio. Besides vibration, the friction at the cutting zone in milling of thin-walled Ti6Al4V will create inconsistencies in the cutting force and increase the surface roughness. Previous researchers reported the use of vegetable oils in machining metal as an effort towards green machining in reducing the undesirable cutting friction. Machining experiments were conducted under Minimum Quantity Lubrication (MQL) using coconut oil as cutting fluid, which has better oxidative stability than other vegetable oil. Uncoated carbide tools were used in this milling experiment. The influence of cutting speed, feed and depth of cut on cutting force and surface roughness were modeled using response surface methodology (RSM) and artificial neural network (ANN). Experimental machining results indicated that ANN model prediction was more accurate compared to the RSM model. The maximum cutting force and surface roughness values recorded are 14.89 N, and 0.161 μm under machining conditions of 125 m/min cutting speed, 0.04 mm/tooth feed, 0.25 mm radial depth of cut (DOC) and 5 mm axial DOC

Response surface methodology integrated modeling of glass fiber reinforced polymer delamination in high speed drilling

Extensive research efforts has been made in the conventional drilling of glass fiber reinforced polymer, where most researches focused in the studies of drilling parameters and thrust force relationship to delamination and tool wear. The effect of drilling generated heat was suggested frequently in these studies, but not many in-depth researches was done in this area. In this paper, an experiment was performed to study the effects of thrust force and drilling generated temperature generated from drilling parameters on delamination factor. A response surface method (RSM) integrated model consist of two phases was developed. The first phase of RSM modelling explained the relationship of drilling parameters with thrust force and drilling generated heat as mediator. The relationship between the mediator and the delamination factor were developed in the second phase of RSM modeling. The final RSM integrated models were validated and it resulted in a low percentage error delamination factor estimation equation from drilling parameters, while understanding and controlling the thrust force and drilling generated temperature

Experimental Study of Electrical Discharge Machine (die sinking) on Stainless Steel 316L Using Design of Experiment

AbstractThe objective of this study is to investigate the influence of Electrical Discharge Machining (EDM) input parameters on characteristics of EDM process. A combination between two advanced materials which stainless steel 316l as workpiece and copper impregnated graphite as electrode have been selected in this study. The copper impregnated graphite is considered as a hybrid material for the electrode which exponentially used in tool and mould making industry. The study was conducted using 2 levels of full factorial method in design of experiments. Analysis of variance (ANOVA) and mathematically modelling were developed for material removal rate (MRR), electrode wear rate (EWR), surface roughness (SR) and dimensional accuracy (DA). The first order model is required to fit dimensional accuracy linear model. However, second order model are required to fit MRR, EWR and SR quadratic models respectively. The result shows that the peak current was the most significant factors to all variable responses. Based on confirmation run, all the results are less than 15% error, thus, indicating the model that were developed for MRR, SR, EWR and Dimensional Accuracy are reasonable accurate

Modeling and optimization of electric discharge machining performances using harmony search algorithm

Electric Discharge Machining (EDM) is one of the widely used non-conventional machining processes for complex and difficult-to-machine materials. EDM technology has been improve significantly and has been developed in many ideas especially in the manufacturing industries that yielded enormous benefits in economic as well as generating keen interest in research area. A major issue in EDM process is how to obtain accurate results of the machining performance measurement value at optimal point of cutting conditions. Thus, this study proposed harmony search algorithm approach for optimization of surface roughness (Ra) in die sinking electric discharge machining (EDM). The mathematical model was developed using regression analysis based on four machining parameters which are pulse on time, peak current, servo voltage and servo speed. The result shows that the optimal solutions for Ra can be found with the minimum values of 1.3031 μm

A survey instrument design to determine the success factors in implementing the end-of-life vehicles (ELVs) management system in Malaysia

This paper presents the design of a survey instrument in order to determine the success factors in implementing the end-of-life vehicles (ELVs) management system in Malaysia. Upon reviewing journal articles and research papers previously conducted in automotive recycling, end of-life vehicles, success factors and green supply chain, a set of preliminary factors was identified.These factors were categorized into seven components, namely the government commitment,stakeholders commitment, resources availability, enforcement and monitoring, education and awareness, market structure and continuous improvement. Thirty items were listed in the questionnaire, where the statements were based on the above said seven factors. Other than that,target respondents and sampling size were also discussed

A Review of Minimum Quantity Lubrication Technique with Nanofluids Application in Metal Cutting Operations

Minimum quantity lubrication (MQL) technique did not only serve as a better alternative to flood cooling during machining but enhance better surface finish, minimizes the cost, reduces the impact loads on the environment and health hazards on the operation personnel. However, the coolant or lubrication media used in MQL technique posed certain restrictions especially at very high cutting speeds where the lubricating oil tends to evaporates as it strikes the already heated cutting tool at elevated temperature. Desire to compensate for the shortcomings of the lubricating media in the MQL technique led to the introduction of nanoparticles in the cutting fluids for use in the MQL lubrication process. Nanoparticles have much higher and stronger temperature-dependent thermal conductivity and enhanced heat transfer coefficient at very low particle concentration, which are key parameters for their enhanced performance in many of the machining applications. Optimizing the nanoparticles concentration leads to efficiency in most of their application. Their ball bearing effect lubrication at the cutting zone through formation of film layer which reduces friction between the contact surfaces thereby reducing cutting force, temperature and tool wear. It has been reported in various studies that nanoparticles introduction in cutting fluids led to excellent machining performance in reduction of cutting forces, reduced tool wear, reduced cutting temperature and improved surface finish of the work piece thereby increasing productivity and reduction of hazards to the health of personnel and the environment better than the pure or conventional MQL process. Thus, the application of various nanoparticles and its performances in metal cutting operations with respect to the cutting forces, surface finish, tool wear and temperature at the cutting zone are evaluated and highlighted