Use of Slurry Colloidal Behavior in Modeling of Material Removal Rates for Copper CMP

An experimental investigation is reported on the grinding of a titanium alloy using electroplated CBN wheels with water-based grinding fluid and wheel surface cleaning fluid applied at high pressures. This work was motivated by applying grinding fluid and wheel surface cleaning fluid both at high pressures for avoiding wheel loading, which is commonly seen in titanium alloy grinding. The objective is to explore the feasibility to grind titanium alloys with electroplated CBN wheels and high pressure wheel surface cleaning fluid for enhancing material removal rates. Straight surface grinding experiments were conducted on titanium alloy blocks in both shallow depth of cut and creep-feed modes. Grinding power, forces, and surface roughness were measured. Specific material removal rates of 8 mm2/s in shallow cut mode and 3 mm2/s at a depth of cut as high as 3 mm in creep-feed mode were achieved without burning and smearing of ground surfaces. It was showed that it is feasible to grind titanium alloys with electroplated CBN wheels at enhanced removal rates by applying grinding and wheel cleaning fluid at high pressures.

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The Material Removal Mechanism in Magnetic Fluid Grinding of Ceramic Ball Bearings

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/pime_proc_1994_208_059_02 ◽

1994 ◽

Vol 208 (1) ◽

pp. 47-59 ◽

Cited By ~ 23

Author(s):

T H C Childs ◽

S Mahmood ◽

H J Yoon

Keyword(s):

Magnetic Fluid ◽

Material Removal ◽

Permanent Magnets ◽

Experimental Studies ◽

Wear Coefficient ◽

Rotating Shaft ◽

Removal Rates ◽

Kinematic Theory ◽

New Process ◽

A Cell

Recently a new process known as magnetic fluid grinding has been developed in Japan which can remove material in the finishing of ceramic balls some fifty times more rapidly than can the lapping processes that are conventionally used. Balls are driven round a cell by a rotating shaft in an arrangement similar to a thrust race but submerged in a magnetic fluid placed above permanent magnets. The magnets and fluid create buoyancy forces that levitate grinding grits in the fluid and also provide the loads for the process, but it is not clear why the process is more effective than lapping. This paper reports on experimental studies of the grinding rates of silicon nitride balls in magnetic fluids loaded with diamond grits and of the motion of the balls through the fluids. The high removal rates occur when skidding occurs between the balls and drive shaft. A kinematic theory is developed to calculate sliding speeds and is used to deduce an abrasive wear coefficient for the process of 0.07 ± 0.02, indicative of two-body abrasion. The high removal rates are a consequence of the large sliding speeds that can be developed, of several metres per second.

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Pitch polishing of silica: correlation between material removal rates and surface finishes

Optifab 2007: Technical Digest ◽

10.1117/12.719782 ◽

2007 ◽

Author(s):

I. Roberts ◽

P. Murray ◽

W. Williams ◽

A. Landis ◽

B. Mullany

Keyword(s):

Material Removal ◽

Removal Rates ◽

Surface Finishes

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Experimental comparison of material removal rates in abrasive waterjet cutting and a novel droplet stream technique

Procedia Manufacturing ◽

10.1016/j.promfg.2020.05.085 ◽

2020 ◽

Vol 48 ◽

pp. 586-592

Author(s):

Benjamin R. Mitchell ◽

Sohani A.R. Demian ◽

Yannis P. Korkolis ◽

Brad L. Kinsey

Keyword(s):

Material Removal ◽

Abrasive Waterjet ◽

Experimental Comparison ◽

Removal Rates ◽

Waterjet Cutting ◽

Abrasive Waterjet Cutting ◽

Droplet Stream

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Mathematical Model for Chip Serration Frequency in Turning of Stainless Steel with Magnetic Damping from Bottom of Tool Shank

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.393.108 ◽

2013 ◽

Vol 393 ◽

pp. 108-114

Author(s):

A.K.M. Nurul Amin ◽

Fawaz Mohsen Abdullah ◽

Muammer Din Arif ◽

Israd H. Jaafar

Keyword(s):

Mathematical Model ◽

Stainless Steel ◽

Material Removal ◽

Control Method ◽

Research Work ◽

Chip Morphology ◽

Work Piece ◽

Removal Rates ◽

Serrated Chip ◽

Tool Shank

Chatter, a violent and often unpredictable relative oscillatory motion between the tool and work-piece, is a serious concern in turning operations. Its occurrence is usually associated with a loud monotonous sound and usually results in increased surface roughness, reduced material removal rates, shortened tool life, and damaged machine-tool bearings. The established theories for chatter are very limited in scope and are often contradicted by empirical evidences. Therefore, chatter avoidance in the past has relied on inefficient techniques like limiting material removal rates or expensive setups such as actuators and ultrasonic vibration damping systems. However, a deeper investigation into chatter formation reveals that chip morphology and segmentation play a significant role during the incidence of chatter. The novel Resonance theory of chatter combines the concept of mode coupling of the machining setup and serrated chip formation, to explain and predict chatter. To validate the postulates of this theory, models for chip serration frequency are essential. At the same time, a reliable and economical chatter control method is required. With this goal, the current research work has developed an empirical mathematical model of chip serration frequency in turning of stainless steel AISI 304 using Response Surface Methodology (RSM). Also, it investigated the influence of damping provided by magnetic field from a permanent ferrite magnet placed beneath the tool shank. The developed chip serration model is in good accord with the experimental data, demonstrating that the empirical model could be used for further chip morphology and chatter analyses.

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