عنوان

Effectiveness of Minimum Quantity Lubrication when Pocket Milling Aluminum Alloy 7075-T6 with Carbide Tools Under High-Speed Machining

Number

TLpq2422174083

.Language of Text, Soundtrack etc

انگلیسی

Title Proper

Effectiveness of Minimum Quantity Lubrication when Pocket Milling Aluminum Alloy 7075-T6 with Carbide Tools Under High-Speed Machining

General Material Designation

[Thesis]

First Statement of Responsibility

Bin Mohd Zainol Amir, Khairul Azreen

Subsequent Statement of Responsibility

Yazid, MZA

Name of Publisher, Distributor, etc.

Universiti Kuala Lumpur

Date of Publication, Distribution, etc.

2020

Specific Material Designation and Extent of Item

165

Dissertation or thesis details and type of degree

M.Phil.

Body granting the degree

Universiti Kuala Lumpur

Text preceding or following the note

2020

Text of Note

This study outlines the effectiveness of minimum quantity lubrication (MQL) in the pocket milling of aluminum alloy 7075-T6 under high-speed machining (HSM) on tool wear, tool life, surface roughness, and chip morphology. MQL is an environmentally friendly approach where a small amount of cutting fluid was sprayed with air aid to the cutting zone in the mist form. Previous studies have found that tool wear is a major challenge to achieve excellent surface quality, tool performance, and favorable chip formation. The experimental work was performed on the computer numerical control (CNC) five axes milling machine with uncoated carbide tools. The machining parameters with three controlled factors and two levels were designed utilizing full factorial design and analysis of variance (ANOVA) was then applied to determine the level of significant machining parameters. Different values of machining parameters involved were 500 and 600 m/min, 0.12 and 0.15 mm/tooth, and 1.40 and 1.70 mm, representing cutting speed, feed rate, and axial depth of cut, respectively. The radial depth of cut of 7 mm was kept constant throughout the experiment. The MQL flow rate was set at 100 mL/h. Dry cutting was done to compare the outcome result with MQL 100 mL/h. After each experiment, the tool flank wear and surface roughness were observed and measured by using an optical microscope and the surface roughness tester, respectively. The tool life criterion was determined when the tool wear failure reached 0.30 mm. The chips collected from all these machining parameters were taken to be examined using an optical microscope. The empirical model of tool life and surface roughness for the MQL and dry cutting was developed with adequate accuracy within the experimental ranges. From the result obtained, MQL 100 mL/h at cutting speed of 500 m/min, feed rate of 0.12 mm/tooth, and axial depth of cut of 1.40 mm stimulated the tool lifespan up to 20.21 minutes. The tool flank wear was observed at all the cutting conditions as a result of adhesion wear mechanism. Uncoated carbide tools with a combination of high cutting speed of 600 m/min and low feed rate of 0.12 mm/tooth produce good surface roughness. At 600 m/min and 0.12 mm/tooth under MQL 100 mL/h, the favorable chip formation was obtained, thus improve surface roughness and diminish severe localization of heat. It is recommended that the flow rate of MQL 100 mL/h should be used for high-speed machining of aluminum alloy 7075-T6 with appropriate machining parameters may potentially lead to economic benefits in terms of fluid cost saving and the better machinability.

Engineering

Mechanical engineering

Bin Mohd Zainol Amir, Khairul Azreen

Yazid, MZA

Electronic name

p

[Thesis]

276903

a

Y