Erween Abdul Rahim

AN ANALYSIS OF SURFACE INTEGRITY WHEN DRILLING INCONEL 718 USING PALM OIL AND SYNTHETIC ESTER UNDER MQL CONDITION

The components being manufactured in the aerospace industry must be capable of being utilized for long periods without failure. Thus, the functional behavior of these machined components is greatly dependent upon their surface integrity. The present work compares the performance of palm oil and synthetic ester on surface integrity during drilling of Inconel 718. The results indicate the substantial benefit of the minimum quantity of lubrication (MQL) by palm oil on microhardness, surface roughness, surface defects and sub-surface deformation.

The performance of modified jatropha-oil based trimethylolpropane(TMP) ester on tribology characteristic for sustainable metalworking fluids (MWFs)

Metalworking fluids (MWFs) are widely used in machining process to improve its performance and product quality. It acts as a coolant and lubricant to reduce heat between the contact of two surfaces. However, commercial MWFs used in the industry were usually from petroleum-based oil which is toxic to the environment, difficult to dispose and caused significant health. Therefore, it is essential to develop a bio-based MWFs to overcome the aforementioned drawbacks. This study was aimed to determine the effect of chemically modified crude jatropha oil (CJO) with trimethylolpropane (TMP) at different molar ratio on tribological characteristic. The produced TMP esters are compared with synthetic ester in terms of wear scar diameter, coefficient of friction and friction torque. From the result, it shows that modified jatropha oil was equivalent with synthetic ester and provided good lubrication and reduce friction and wear.

Laser Assisted Machining of Titanium Alloys

Laser assisted machining is categorized in preheat machining process. The laser beam used to heat up work materials is very flexible in providing a localized heat area. However the combination between two processes which has totally different fundamental has contributed to complex processing characteristics. In the case of hard to machined metal processing, problems in surface integrity and accuracy are frequently arise. Tool ware and work material properties changes are some of the issue that drove engineers and researchers to seek for optimized processing parameters. This chapter introduces resent finding in research done on laser assisted machining (LAM). Focus is given on laser assisted mechanical machining consist of laser assisted milling (LAM) and laser assisted turning (LAT).

Application of Minimum Quantity Lubrication when Drilling Nickel-Based Superalloy at High Cutting Speed

Nowadays, an increase on demands of aerospace components has led to implementation of high speed machining (HSM). The principal factors in the performance of aerospace materials are strength-to-weight ratio, fatigue life, fracture toughness, survivability and of course, reliability. However, when HSM is coupled with dry or near dry machining, it will present considerable technical challenges to the manufacturing sector especially when the integrity of the machined surface is concerned. In this investigation, the effect of high speed drilling (HSD) conditions on the performance and surface integrity of Inconel 718 were studied. Hole was drilled individually using TiAlN coated carbide insert drill (14 mm in diameter) under minimum quantity of lubrication (MQL) condition. Results showed that uniform flank wear and chipping were the dominant tool failure modes. Moreover, the results showed an increase in cutting temperature with increasing cutting speed and feed rate. Thrust force and torque decreased linearly with the increasing cutting speed but significantly increased when higher feed rate is employed. Cutting speed significantly influenced the distribution of surface roughness value. Variations of hardness readings were recorded beneath the machined surfaces, they were due to the hardening effects caused by concentration of high temperature and stresses on the workpiece.

Effect of MQL Liquids on Surface Integrity when High Speed Drilling Titanium Alloy

This paper describes the results of application of different MQL liquids (synthetic ester and palm oil) to high speed drilling of Ti-6Al-4V. The investigation was focused on the surface integrity of the machined surface. It was found that palm oil could be a viable alternative to the synthetic ester for MQL liquid application.

Surface Integrity when Drilling Nickel-Based Superalloy under MQL Supply

The components being manufactured in aerospace industry must be capable of being utilized for long periods without failure. Thus, the functional behavior of these machined components is greatly dependent upon their surface integrity. The present work compares the performance of palm oil and synthetic ester on surface integrity when drilling of Inconel 718. The results indicate the substantial benefit of MQL by palm oil on microhardness, surface roughness, surface defects and sub-surface deformation.

Surface Integrity in MQL Drilling Nickel-Based Superalloy

Nickel-based superalloys remain the most widely used of all materials in aerospace industry, contributed over 50 % of the weight of a jet engine. In machining of any jet engine components, it is necessary to satisfy the surface quality or surface integrity requirements to facilitate high reliability components. In the present study, surface integrity of Inconel 718 was studied when drilling under different lubricants. The holes were drilled individually using indexable AlTiN coated carbide drill under minimum quantity of lubricant (MQL) conditions. The results demonstrated that the machining conditions and lubricants strongly influence the surface integrity. The surface roughness decreases with the increase in cutting speed and increases with the increase in feed rate. Microhardness profiles indicated that the subsurface deformation extends up to a 100 and 150 μm for palm oil and synthetic ester, respectively underneath the machined surface. Pit holes, cavities, grooves, microcracks and surface smearing were the dominant surface damages criteria for all cases.

Effect of Heat Compression on the Tensile Strength of PALF/Sugarcane Bagasse for Disposable Plate

This paper presents the results of heat compression effect on tensile properties in manufacturing process of disposable plate from Pineapple Leaf Fibers (PALF) based material. The plate was made of PALF and sugarcane bagasse waste as alternatif to polystyrenes to promote the green technology efford on food packaging material. Two different spesimens were produced with different composition of PALF/sugarcane bagasse, N2T8 (20% Pineapple leaf fiber and 80% sugarcane bagasse and N8T2 (80% pineapple leaf fiber and 20% sugarcane bagasse). The specimens were produced on a hot press machine at different compressing temperature, 50°C, 100°C and 150°C with constant pressure of 0.024 MPa at 10 minutes. Tensile and tearing tests were carried out on the specimens to determine the tensile and tearing properties. The results shown that the N2T8 speciment compressed at 50°C gives higher tensile and tearing strength of 22 MPa and 2 MPa ,respectively. This range of properties is expected to be good enough for the requirement of disposable plate and it has a potential as a raw material for strength and lightweight of disposable plate manufacturing.

Performance Investigation of Modified Turning Tool Holder for MQL Application

Some machining process requires coolant to reduce the cutting temperature and helps to flush away the chips from the cutting zone. However, conventional flood coolant possesses some issues towards workers and the environment, regarding health and waste management. The implementation of Minimal Quantity Lubrication (MQL) as an alternative technique seems to be promising although the effectiveness of this technique were influenced by several factor. In turning process for instance, the distance of nozzle to the cutting zone contributes to the variation of machining performance. This study is to compare the effect on cutting performance between two internal MQL nozzle designs. The cutting tool holder were modified to have two internal MQL oil channel. The oil channel design were tested and the performance was evaluated in terms of cutting speed and cutting temperature for different cutting speed, feed rate and depth of cut. The result shows that the single channel performs better in terms of cutting force while dual channel significantly improve the cutting temperature.

Performance of Tools Design when Helical Milling on Carbon Fiber Reinforced Plastics (CFRP) Aluminum (Al) Stack

Hole making process is not strictly to the drilling technique where others machining could also influence to the quality in CFRP hole.Therefore, helical milling process becomes as an alternative method to produces bore on CFRP plate thus minimizing the defects. The common defects on CFRP are delamination, splintering and cracking. Meanwhile, if the CFRP stacking together with aluminum plate, burr at exit hole of aluminium plate is produced. Therefore, it is essential to control the critical machining parameters to assure a good quality of the hole. The main objective of this project is to improve the hole quality of CFRP/AL stack in terms of surface roughness using helical milling technique. In addition the cutting force and temperature will be measured as well. There are three levels of cutting speeds; two levels of feed rate and depth per helical path are made accordingly to helical milling characteristics. It was found that all tool design exhibit comparable performance for helical milling process on CFRP/Al stack.