Burr formation in short hole drilling with minimum quantity lubrication

Laser-assisted micromilling is a promising micromachining process for difficult-to-cut materials. Laser-assisted micromilling uses a laser to thermally soften the workpiece in front of the cutting tool, thereby lowering the cutting forces, improving the dimensional accuracy, and reducing the tool wear. Thermal softening, however, causes the workpiece material to adhere to the tool and form a built-up edge. To mitigate this problem and to enhance micromachinability of the workpiece in laser-assisted micromilling, this article investigates the following lubrication and cooling methods: (1) minimum quantity lubrication and (2) vortex tube cooling. Experiments utilizing the two methods are carried out on a difficult-to-cut stainless steel (A286), and the surface morphology, tool condition, burr formation, groove dimensional accuracy, surface finish, and cutting forces are analyzed. Results show that the combination of laser-assisted micromilling and minimum quantity lubrication yields the least amount of tool wear, lower resultant force, better groove dimensional accuracy, and no built-up edge. While vortex tube cooling with laser-assisted micromilling produces smaller burrs compared to minimum quantity lubrication, it yields larger changes in groove dimensions and is characterized by built-up edge formation. Possible physical explanations for the experimental observations are given.

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Modelling, Simulation and Compensation of Thermomechanically Induced Deviations in Deep-Hole Drilling with Minimum Quantity Lubrication

Lecture Notes in Production Engineering - Thermal Effects in Complex Machining Processes ◽

10.1007/978-3-319-57120-1_10 ◽

2017 ◽

pp. 181-218 ◽

Cited By ~ 1

Author(s):

D. Biermann ◽

H. Blum ◽

I. Iovkov ◽

A. Rademacher ◽

K. Rosin ◽

...

Keyword(s):

Minimum Quantity Lubrication ◽

Hole Drilling ◽

Deep Hole ◽

Deep Hole Drilling ◽

Minimum Quantity ◽

Modelling Simulation

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Workpiece Thermal Distortion in Minimum Quantity Lubrication Deep Hole Drilling—Finite Element Modeling and Experimental Validation

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4005432 ◽

2012 ◽

Vol 134 (1) ◽

Cited By ~ 16

Author(s):

Bruce L. Tai ◽

Andrew J. Jessop ◽

David A. Stephenson ◽

Albert J. Shih

Keyword(s):

Heat Flux ◽

Finite Element ◽

Heat Carrier ◽

Three Dimensional ◽

Minimum Quantity Lubrication ◽

Hole Drilling ◽

Bottom Surface ◽

Thermal Distortion ◽

Element Analysis ◽

Minimum Quantity

This paper presents the three dimensional (3-D) finite element analysis (FEA) to predict the workpiece thermal distortion in drilling multiple deep-holes under minimum quantity lubrication (MQL) condition. Heat sources on the drilling hole bottom surface (HBS) and hole wall surface (HWS) are first determined by the inverse heat transfer method. A 3-D heat carrier consisting of shell elements to carry the HWS heat flux and solid elements to carry the HBS heat flux has been developed to conduct the heat to the workpiece during the drilling simulation. A thermal–elastic coupled FEA was applied to calculate the workpiece thermal distortion based on the temperature distribution. The concept of the heat carrier was validated by comparing the temperature calculation with an existing 2-D advection model. The 3-D thermal distortion was validated experimentally on an aluminum workpiece with four deep-holes drilled sequentially. The measured distortion on the reference point was 61 μm, which matches within uncertainty the FEA predicted distortion of 51 μm.

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An Experimental Investigation of Inclined Hole Drilling for CFRP Under Various Lubrication Techniques

Volume 2: Advanced Manufacturing ◽

10.1115/imece2018-87550 ◽

2018 ◽

Author(s):

Sathish Kannan ◽

Salman Pervaiz ◽

Abhishek Ghoshal

Keyword(s):

Critical Role ◽

Weight Ratio ◽

Minimum Quantity Lubrication ◽

Industrial Applications ◽

Burr Formation ◽

Hole Drilling ◽

Machining Performance ◽

Dry Cutting ◽

Machine Material ◽

Drilling Operation

Carbon Fiber Reinforced Polymer (CFRP) is favoured in the aerospace, automotive, structural and sports-based industries due to its high strength-to-weight ratio, rigidity and comparatively higher stiffness. CFRP is termed as a difficult-to-machine material due to the problems associated with its machined quality, surface integrity and tooling cost. As per the industrial applications and requirements, drilling operation is mainly conducted on the CFRP material. Due to the layered structure of CFRP material, drilling operation produces defects such as delamination, burr formation, uncut fiber, fiber breakout and fiber pullout etc. These defects are mainly observed at the entrance and exit of the drilled hole. This poor surface finish and associated defects can play a very critical role towards the load carry capacity, reliability and service life of the final product, especially if the component is more prone to experience fatigue type of loading. There are several applications where the requirement is to have a hole at some inclination angle. To facilitate and develop the understanding of CFRP machining performance under inclined drilling, the presented study is focused on the drilling of inclined hole. The study will also incorporate different lubrication strategies such as dry cutting, conventional flood and minimum quantity lubrication (MQL) during the drilling of CFRP material.

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Influence of Minimum Quantity Lubrication on Burr Formation in Milling

Burrs - Analysis, Control and Removal ◽

10.1007/978-3-642-00568-8_15 ◽

2009 ◽

pp. 139-146 ◽

Cited By ~ 1

Author(s):

U. Heisel ◽

M. Schaal ◽

G. Wolf

Keyword(s):

Minimum Quantity Lubrication ◽

Burr Formation ◽

Minimum Quantity

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Workpiece Temperature During Deep-Hole Drilling of Cast Iron Using High Air Pressure Minimum Quantity Lubrication

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4024036 ◽

2013 ◽

Vol 135 (3) ◽

Cited By ~ 14

Author(s):

Bruce L. Tai ◽

David A. Stephenson ◽

Albert J. Shih

Keyword(s):

Heat Flux ◽

Cast Iron ◽

Heat Generation ◽

Minimum Quantity Lubrication ◽

Air Pressure ◽

Hole Drilling ◽

Deep Hole ◽

Deep Hole Drilling ◽

Workpiece Temperature ◽

Minimum Quantity

This research investigates heat generation and workpiece temperature during deep-hole drilling of cast iron under a high air pressure minimum quantity lubrication (MQL). The hole wall surface (HWS) heat flux, due to drill margin friction and high temperature chips, is of particular interest in deep-hole drilling since it potentially increases the workpiece thermal distortion. This study advances a prior drilling model to quantify the effect of higher air pressure on MQL drilling of cast iron, which is currently performed via flood cooling. Experiments and numerical analysis for drilling holes 200 mm in depth on nodular cast iron work material with a 10 mm diameter drill were conducted. Results showed that the low drill penetration rate can cause intermittent chip clogging, resulting in tremendous heat; however this phenomenon could be eliminated through high air pressure or high feed and speed. Conversely, if the drilling process is stable without chip clogging and accumulation, added high air pressure is found to have no effect on heat generation. The heat flux though the HWS contributes over 66% of the total workpiece temperature rise when intermittent chip clogging occurs, and around 20% to 30% under stable drilling conditions regardless of the air pressure. This paper demonstrated the significance of HWS heat flux and the potential of high air pressure used in conjunction with MQL technology.

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Burr Formation in milling with minimum quantity lubrication

Production Engineering ◽

10.1007/s11740-008-0138-9 ◽

2008 ◽

Vol 3 (1) ◽

pp. 23-30 ◽

Cited By ~ 10

Author(s):

U. Heisel ◽

M. Schaal ◽

G. Wolf

Keyword(s):

Minimum Quantity Lubrication ◽

Burr Formation ◽

Minimum Quantity

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An investigation on the top burr formation during Minimum Quantity Lubrication (MQL) assisted micromilling of copper

Materials Today Proceedings ◽

10.1016/j.matpr.2020.02.379 ◽

2020 ◽

Vol 26 ◽

pp. 1809-1814

Author(s):

Suman Saha ◽

A. Sravan Kumar ◽

Sankha Deb ◽

Partha Pratim Bandyopadhyay

Keyword(s):

Minimum Quantity Lubrication ◽

Burr Formation ◽

Minimum Quantity

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Effect of Minimum Quantity Lubrication on Tool Wear and Surface Roughness in Micro-Milling

ASME 2009 International Manufacturing Science and Engineering Conference, Volume 2 ◽

10.1115/msec2009-84353 ◽

2009 ◽

Cited By ~ 2

Author(s):

Kuan-Ming Li ◽

Shih-Yen Chou

Keyword(s):

Surface Roughness ◽

Tool Wear ◽

Machine Tools ◽

Minimum Quantity Lubrication ◽

Micro Milling ◽

Burr Formation ◽

Cutting Fluids ◽

Electronic Components ◽

Minimum Quantity ◽

Aspect Ratios

Micro-milling is a suitable technique for manufacturing of microstructures with high aspect ratios and intricate geometries. The application of the micro-milling process in cutting hardened tool steel is particularly challenging. The low strength of the miniaturized end mills implies accurate control of the chip load in order to prevent the tool break and product dimension errors, which requires high positioning accuracy. It is known that the application of cutting fluids can improve the performance of machining operations. However, the supply of cutting fluids in a conventional way is not appropriate for miniature machine tools due to the plentiful electronic components used to construct micro-scale machine tools. Minimum quantity lubrication (MQL) presents itself as a possible alternative for micro-cutting with respect to the minimum impact on the electronic components as well as low tool wear, better heat dissipation, and machined surface quality in metal cutting. This study compares the mechanical performance of MQL to completely dry condition for the micro-milling of SKD 61 steel based on experimental measurements of tool wears and surface finish. The effect of MQL on the burr formation is also observed. Results indicate that the use of MQL leads to reduced tool wears, better surface roughness, and less burr formation.

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