Ahmad Razlan Yusoff

Determining optimum EDM parameters in drilling a small hole by Taguchi method

Electro Discharge Machining (EDM) process uses electric sparks to generate high temperature and melts the workpiece material. In drilling process of EDM, electro thermal mechanism between electrode and workpiece creates a hole. The present study performs Taguchi method to search the optimal process parameters for high speed super drill machine that was used to make a small hole from aluminium material. An Orthogonal (OA) array, main effect, Signal-to-Noise (S/N) ration and Analysis of Variance (ANOVA) were employed to investigate the hole size of the copper electrode of diameter 1.0 mm penetration. The optimum EDM hole process can be established through this method and the major parameters that effect the hole enlarge can be also detected and verified the effectiveness through experimental results.

Flank Wear Characterization in Aluminum Alloy (6061 T6) With Nanofluid Minimum Quantity Lubrication Environment Using an Uncoated Carbide Tool

This study is focused on the categorical analysis of flank wear mechanisms in end milling of aluminum alloy AA6061 with minimum quantity lubrication (MQL) conditions using nanofluid. Wear mechanisms for the water-based TiO2 nanofluid with a nanoparticle volume fraction of 1.5% are compared with conventional oil-based MQL (0.48 ml/min and 0.83 ml/min) using an uncoated cemented carbide insert. Micro-abrasion, micro-attrition, and adhesion wear leading to edge chipping are identified as the main wear mechanisms. Aluminum deposits on the tool flank surface are observed. Results show that the water-based nanofluid shows potential as a capable MQL cutting media, in terms of tool wear, replacing the conventional oil-based MQL.

Experimental Validation of Chatter Stability for Variable Helix Milling Tools

The occurrence of self-excited vibrations during machining is known as regenerative chatter, and this phenomenon can severely limit the machining productivity. By modifying and optimising the tools pitch and helix geometry, this regenerative chatter can be suppressed to increase material removal rate. In this paper, experimental verification of an optimised variable helix and variable pitch tools is presented. The geometry was optimised using a Differential Evolution (DE) algorithm. Based on stability diagrams of original and optimised milling tools, the experiment was conducted and the results were compared when chatter occurred. The optimised cutter significantly outperformed the original cutter in term of chatter suppression.

Review of Aluminum Chip Machining Using Direct Recycling Process

This paper reviews the chain of aluminum Direct Recycling process. Direct Recycling is one of intelligent process to recycle the aluminum waste. The current method for recycle waste aluminum, was affect on the environmental issues. This paper focus on the aluminum waste from machining process, also called chips produced from turning and milling process. From chip collected, next compaction process are compressed to the certain amount pressure for consolidating the materials. Lastly to produce a new material, the process is extrusion process. The most important issue to get a quality of a product is, how to control the pressure during both of process. During this process also available in hot and cold condition. From review, it was that cold compaction process more popular implemented compared to hot compaction. Then almost researchers applied hot extrusion it is because to cover sintering process.

Bouc-Wen Model Parameter Identification for a MR Fluid Damper Using Particle Swarm Optimization

This paper present parameter identification fitting which are employed into a current model. Irregularity hysteresis of Bouc-Wen model is colloquial with magneto-rheological (MR) fluid damper. The model parameters are identified with a Particle Swarm Optimization (PSO) which involves complex dynamic representation. The PSO algorithm specifically determines the best fit value and decrease marginal error which compare to the experimental data from various operating conditions in a given boundary.

Multiobjective Optimization of Milling Tool Geometry for Chatter Suppression and Productivity Improvement

In this paper, productivity and self-excited vibration are simultaneously optimized using multiobjective optimization in cutting process. At high material removal rate, machining processes accelerates tool wear, poor surface finish and failure of machine parts. The effect of self-excited vibration or chatter prevents high machining productivity. This chatter vibration can be avoided by modifying tool geometry at low material removal rate but not at high productivity. To compensate material removal rate and chatter, multiobjective optimization is applied using ε-constraint algorithm to achieve a Pareto front solution. Differential Evolution as intelligent optimization algorithm is shown better results than traditional technique of Sequential Quadratic Programming.

Comparison of Cooling Performance between High Thermal Conductivity Steel (HTCS 150) and Hot Work Tool Steel (SKD 61) Insert for Experimental Tool Using Finite Element Analysis

In hot stamping, the tool cooling system plays an important role in optimizing the process cycle time as well as maintaining the tool temperature distribution. Since the chilled water is forced to circulate through the cooling channels, there is a need to find the optimal parameters of the cooling channels that will cool down the tool efficiently. In this research paper, the cooling channel parameters that significantly influence the tool cooling performance such as size of the cooling holes, distance between the cooling holes and distance between the cooling holes and the tool surface contour are analyzed using the finite element method for both static and thermal analysis. Finally the cooling performance of two types of materials is compared based on the optimized cooling channel parameters.

Optimization of Electro Discharge Machining Parameters for Drilling Titanium in Small Holes Using Taguchi Method

Electro discharge machining (EDM) is a process that use an electric sparks to generate the high temperature and melts the work piece. One of the processes using this method is drilling process. By using this concept, an electro thermal mechanism between electrode and work piece can creates the hole enlargement and the size of the hole its depend on the diameters of electrode are used. The present study performs Taguchi method to investigate the optimal process parameters for high speed super drill machine that was used to make a small hole from titanium alloy (Ti-6: ASTM B348 Grade 5) by using 2.0 mm diameter of copper electrodes. In this experiment, the process parameters namely, current pulse off; maximum current and standard voltage level were selected to optimize. An orthogonal array L9 was employed to analyze the material removal rate (MRR) of the copper electrode of diameter 2.0 mm penetration. The optimum EDM hole process can be established through this method and the major parameters that effect the MRR can be also detected and verified the effectiveness through experimental results.

Taguchi Method Approach for Recyling Chip Waste from Machining Aluminum (AA6061) Using Hot Press Forging Process

This paper investigates the recycling waste aluminum alloy 6061 from high speed machine (HSM) machine using hot forging process. Hot forging process able to recover the grain structure of material by controlling certain pressure and temperature. The experiments conducted by Taguchi method design. Three factors selected are chip size, operating temperature and operating pressure with three levels for each factor. Both factors for operating temperature and pressure direct control from hot forging machine. The chip sizes are prepared from HSM machine using by three machine parameters, which are constant cutting speed and manipulate three levels for each parameter for feed rate and depth of cut. The final result between reference and experiment specimen shows the close gap in the tensile test. The main effect, signal noise ratio and analysis of variance were employed to investigate the results and the optimum parameters for hot forging process can be established. It can be concluded that the hot forging process able to recycle waste (chip) aluminum compared to the current recycling aluminum process.

A comparative study on performance of CBN inserts when turning steel under dry and wet conditions

Cutting fluids is the most unsustainable components of machining processes, it is negatively impacting on the environmental and additional energy required. Due to its high strength and corrosion resistance, the machinability of stainless steel has attracted considerable interest. This study aims to evaluate performance of cubic boron nitride (CBN) inserts for the machining parameters includes the power consumption and surface roughness. Due to the high single cutting-edge cost of CBN, the performance of significant is importance for hard finish turning. The present work also deals with a comparative study on power consumption and surface roughness under dry and flood conditions. Turning process of the stainless steel 316 was performed. A response surface methodology based box-behnken design (BBD) was utilized for statistical analysis. The optimum process parameters are determined as the overall performance index. The comparison study has been done between dry and wet stainless-steel cut in terms of minimum value of energy and surface roughness. The result shows the stainless still can be machined under dry condition with 18.57% improvement of power consumption and acceptable quality compare to the wet cutting. The CBN tools under dry cutting stainless steel can be used to reduce the environment impacts in terms of no cutting fluid use and less energy required which is effected in machining productivity and profit.