Mohd Amri Sulaiman

Cutting Performances of Coated PVD in High Speed End Milling of Aged Inconel 718

Inconel 718 is a material exhibiting characteristic that are able to maintain strength and integrity at elevated temperatures, but it is well known as a material with poor machinability. This paper presents a study of the performance in high speed machining of TiAlN/AlCrN nanomultilayer PVD coated Inconel 718 with minimum lubrication. Investigations have been made into the effects of cutting speed, feed rate and depth of cut (DOC) on the tool life. A toolmakers microscope and a scanning electron microscope (SEM) were used to examine the tool wear and chemical attrition, respectively, on the cutting tool during machining. In the machining of aged Inconel 718, the cutting tool experienced attrition, abrasion and notch wear throughout the experiment. Notch wear was found to be the dominant failure mode during milling; this wear appeared severe when localized flank wear reached the critical zone. The influence of radial depth despite the cutting speed, well known as having the most significant effect on tool life, is also discussed.

Evaluation of the Surface Integrity when Machining LM6 Aluminum Metal Matrix Composites Using Coated and Uncoated Carbide Cutting Tools

Metal matrix composite is composite material that combines the metallic properties of matrix alloys and additional element to reinforce the product. This paper evaluates the machining performance of uncoated carbide and coated carbide in terms of surface integrity during end milling of LM6 aluminium MMC. The parameter of cutting speed, feed rate and axial depth of cut were kept constant at 3000 rpm spindle speed, 60 mm/min feed rate and 0.5 axial dept of cut. The radial depth of cut were varied from 0.01mm to 0.1 mm. The results indicated that uncoated carbide show the better performance in terms of surface roughness and surface profile, as compared to coated carbide. On the other hand, coated carbide cutting tools suffered with built-up-edge formation at the tool edge, hence caused shearing effect and deterioration at the tool-chip interface. This study is expected to provide understanding of machining metal matrix composites based materials.

Analysis of Tool Performance during Ball-end Milling of Aluminium Alloy 6061-T6

This article presents the tool wear mechanism when machining Aluminium alloy 6061-T6 with PVD coated carbide under dry cutting condition. Cutting parameters selected were cutting speed, Vc = 115-145 m/min; feed rate fz = 0.15-0.2 mm/tooth and depth of cut, ap = 0.5-0.75 mm. The result showed the tool life of PVD TiAlN ranged from 11 to 97 min. Full factorial approach was employed to exhibit relationship between parameter input and output. From the analysis, cutting speed was found to be the most significant factor for tool performance followed by feed rate and depth of cut. It was also found that most of failure modes occurred were notch wear and flaking near those found near depth of cut line.

2308 Effect Cutting Parameters on Surface Roughness during End Milling of AISI D2 Tool Steel

The material of AISI D2 tool steel contains high carbon and chromium alloyed is referred as difficult material to be machining. This research was performed to identify the implications of machining variables in High Speed Machining of milling using material of AISI D2 tool steel with inserted end mill tool. The experiment work was carried out using Box-Behken techniques, a part of response surface methodology (RSM) approach by generating from the Design Expert Software. The effect of milling parameters that are cutting speed, feed rate, and width of cut were studied to evaluate their effects on surface roughness. In this study, the cutting speed, feed rate, and width of cut were in the range of 100-200 m/min, 0.1-0.3 mm/tooth, 0.2mm and 2.0-8.0 mm respectively. This study prove that the parameters that give the most significant to the surface roughness in descending order starting from cutting speed, feed rate and width of cut. The effects of input factors on the response were identified by using analysis of variance ANOVA. The responds of surface roughness then simultaneously optimized. The optimum parameters that yield the best surface roughness are cutting speed of 150 m/min, feed rate of 0.1 mm/min and the width of cut of 8mm that produce the surface roughness of 0.186 μm.

Effects of Helix Angle on Cutting Performance for Machining Thin-Wall Aerospace Monolithic Component

The thin-walled component is mostly used in the aerospace industry. During machining the thin-walled components, deflection of wall occurs and causes the surface dimensional error. This paper focuses on the effect of end mill helix angle on the surface dimensional error and surface roughness when machining thin wall structure. End mills uncoated carbide were fabricated with a difference helix angle which are 25°, 30°, 35°, 40° and 45°. The results show, helix angle 35° produce smaller surface dimensional error and smoothest followed by 40°, 45°, 30° and 25°. The smaller helix angle provided high cutting force that causes more surface dimensional error due to chatter and reduction of contact time when then end mill engage with the workpiece material. Results from this research help to guide the machinist to machine thin-wall component with the right cutting tool.

Finite Element Model of Trimming CFRP Aerospace Composites

Carbon Fiber Reinforced Plastics (CFRP) exhibit superior characteristics such as high specific strength, high specific modulus, fatigue strength and endurance. During the manufacture of components from CFRP, it is usually necessary to carry out a post-machining step. Generally, after curing process, the parts will be trimmed in order to meet the required tolerances. Due to the heterogeneous composition and anisotropy of composite materials, machining procedures can damage the material in ways that directly affect its mechanical properties. Currently a costly try and error approach is employed to determine the optimal process conditions. Thus, this study focused on numerical modelling of machining CFRP composites using cross-nick router. A set of machining tests were performed in order to validate the accuracy of the model. Good agreement between simulation and experimental results show the validity of the model in handling real-field problems. The proposed numerical modeling technique can be used as an input in the process planning and decision making levels.