Babur Ozcelik

Environmentally Friendly Machining: Vegetable Based Cutting Fluids

A wide variety of cutting fluids are commercially available in the cutting fluid suppliers in order to provide machining performances for a number of industries. In machining, mineral, synthetic and semi-synthetic cutting fluids are widely used but, recently, uses of vegetable based cutting fluids have been increased. Although, these cutting fluids are beneficial in the industries, their uses are being questioned nowadays as regards to health and environmental issues. Cutting fluids are contaminated with metal particles and degradation products which diminish the effectiveness of cutting fluids. To minimize the adverse environmental effects associated with the use of cutting fluids, the hazardous components from their formulations have to be eliminated or reduced to the acceptable level. In addition, mineral based cutting fluids are going to be replaced with vegetable based cutting fluids since they are environmentally friendly. Today to diminish the negative effects associated with cutting fluids, researchers have developed new bio based cutting fluids from various vegetable oils. This chapter has also focused on environmental conscious machining such as dry cutting, machining with minimum quantity lubricant and especially machining with vegetable based cutting fluids including other types of cutting fluids. Literatures associated with types of cutting fluids have also been presented in this chapter.

Evaluation of New Vegetable-Based Cutting Fluids on Thrust Force and Surface Roughness in Drilling of AISI 304 Using Taguchi Method

This study focused on both formulation of vegetable-based cutting fluids (VBCFs) and machining with these cutting fluids. For this purpose, characterizations of chemical and physical analyses of these formulated cutting fluids were carried out. Performances of five cutting fluids, three VBCFs developed from crude and refined sunflower oils, and two commercial types, were investigated for thrust force and surface roughness during drilling of AISI 304 with HSS-E tool. Spindle speed, feed rate and drilling depth were considered as machining parameters. L9 orthogonal array was used for the experiment plan. Results were evaluated using regression analysis and ANOVA.

Optimization of surface roughness in drilling using vegetable‐based cutting oils developed from sunflower oil

Purpose – The purpose of this paper is to investigate the performance of four cutting oils, two different vegetable‐based cutting fluids developed from refined sunflower oil and two commercial types (semi‐synthetic and mineral), for surface roughness during drilling of AISI 304 austenitic stainless steel with HSSE tool.Design/methodology/approach – L9 (33) orthogonal array was used for the experiment plan. Spindle speed, feed rate and drilling depth were considered as machining parameters.Findings – Results were evaluated statistically. Mathematical models based on cutting parameters were obtained from regression analyses to predict surface roughness. ANOVA was used to determine the effect of the cutting parameters on the surface roughness. The performance results were found to be better for vegetable‐based cutting oils than that of commercial ones.Originality/value – The paper reports on the use of refined sunflower oil in drilling stainless steel.

Comparison of Dry and Wet End Milling of AISI 316 Stainless Steel

The aim of this study is to investigate the performance of dry and wet cutting during end milling of AISI 316 stainless steel. The milling experiments were carried out at two stages. First stage was conducted at a constant feed rate of 0.25 mm/rev, depth of cut of 0.3 mm, and varying cutting speeds of 100, 150, and 200 m/min. Second stage was conducted at a constant cutting speed of 200 m/min, depth of cut of 0.3 mm, and varying feed rates of 0.1, 0.2, and 0.3 mm/rev. The experiments were conducted to compare the tool wear, milling force components and surface roughness under various operating conditions. The progress of the tool wear was analysed with scanning electron microscopy (SEM) of the cutting edge. The results obtained from the experimental studies have confirmed that the presence of semisynthetic cutting fluid has negative impact in milling of AISI 316. The catastrophic failure of cutting tool in wet milling may be due to the intense thermal stress caused by the application of semisynthetic cutting fluid.

Evaluation of handling results of various materials using a non‐contact end‐effector

A non‐contact end‐effector was applied to lift three different materials which have different physical properties. These materials are mica (as rigid material), carton (as semi‐rigid material) and non‐rigid material (woven fabric). This end‐effector operates on the principle of generating a high‐speed air flow between nozzles and the specimen surface thereby creating a vacuum which levitates the materials with no mechanical contact. In this paper, the handling results of these materials are compared with each other. The changes in the physical behavior of lifting materials were observed during the experimental work. The effect of the various air flow rates on the non‐contact handling clearance gap between the nozzle and the materials were also investigated. As a result, it was observed that the non‐contact end‐effector could be applied to handle different flat materials.

A non-contact end-effector for the handling of garments

In order to handle a material with either a delicate surface or an air permeable structure, a novel nozzle was designed and developed. This nozzle utilises the phenomena of the radial air outflow. It is envisaged that this new nozzle will handle materials by eliminating surface marking and air permeable structure problems.

Optimization of machining parameters during micro-milling of Ti6Al4V titanium alloy and Inconel 718 materials using Taguchi method

This study focused on the optimization of micro-milling parameters for two extensively used aerospace materials (titanium and nickel-based superalloy). The experiments were planned using Taguchi experimental design method, and the influences of spindle speed, feed rate and depth of cut on machining outputs, namely, tool wear, surface roughness and cutting forces, were determined. Tool wear, surface roughness and cutting forces measured in micro-milling of Ti6Al4V titanium alloy and Inconel 718 workpiece materials were optimized by employing Taguchi’s signal-to-noise ratio. The percentage contribution of micro-milling parameters, namely, spindle speed, feed rate and depth of cut, on tool wear, surface roughness and cutting forces was indicated by analysis of variance. The regression models identifying the relationship between the input variables and the output responses were also fitted using experimental data to predict output responses without conducting the experiments. Efficiency of regression models was determined using correlation coefficients, and the predicted values were compared with experimental results. From results, it was concluded that the established regression models could be employed for predicting tool wear, surface roughness and cutting forces in micro-milling of Ti6Al4V titanium alloy and Inconel 718 workpiece materials.

Influences of Injection Conditions on Strength Properties of Recycled and Virgin PBT/PC/ABS

Effect of conditions on the rheological and mechanical properties of virgin and recycled poly(butylene terephthalate)/polycarbonate/acrylonitrile-butadiene-styrene (PBT/PC/ABS) blends was investigated in injection molding by using Taguchis experimental design. PBT, PC, and ABS polymers were compounded in an extruder to obtain ternary blends. Blend was recycled five times. Injection pressure, holding pressure, and injection temperature were taken into consideration as the input. Ratio of signal-to-noise (S/N) was employed to determine whether optimum conditions of control inputs could be used to achieve the highest properties. Analysis of variance was used to determine how inputs affect outputs.

Micro-milling performance of AISI 304 stainless steel using Taguchi method and fuzzy logic modelling

In this study, micro-milling of AISI 304 stainless steel with ball nose end mill was conducted using Taguchi method. The influences of spindle speed, feed rate and depth of cut on tool wear, cutting forces and surface roughness were examined. Taguchi’s signal to noise ratio was utilized to optimize the output responses. The influence of control parameters on output responses was determined by analysis of variance. In this study, the models describing the relationship between the independent variables and the dependent variables were also established by using regression and fuzzy logic. Efficiency of both models was determined by analyzing correlation coefficients and by comparing with experimental values. The results showed that both regression and fuzzy logic modelling could be efficiently utilized for the prediction of tool wear, cutting forces and surface roughness in micro-milling of AISI 304 stainless steel.

Recyclability of Polyethylene/Polypropylene Binary Blends and Enhancement of Their Mechanical Properties by Reinforcement with Glass Fiber

In this work, glass-fiber-reinforced and unreinforced polypropylene-polyethylene blends were obtained to examine the effects of recycling process on the mechanical and chemical properties. Tensile strength, flexural strength, izod impact strength, and melt flow index tests were applied to test specimens. After recycling process, the mechanical properties of both glass-fiber-reinforced and unreinforced polypropylene-polyethylene blends declined. Decrease of the mechanical properties of the recycled blends was supported by scanning electron microscopy morphologies revealed separation and degradation in matrix phase. It was observed that adding glass fiber in polypropylene-polyethylene led to the improvement in mechanical properties except impact strength.