Role of Chip Serration Frequency in Chatter Formation during End Milling Operation of Stainless Steel

Experimental investigations have been conducted on the chips and common types of discreteness in the form of serrated saw teeth (primary or secondary) have been identified. It has been observed that the chip formation process has a discrete nature, associated with the periodic shearing process of the chip during machining of stainless steel. Mechanism of formation of these teeth has been studied and the frequency of their formation has been determined. The different modes of the vibrating components of the vertical machining centre have been extracted by modal analysis and the vibration responses during cutting conditions have also been recorded using an online monitoring data acquisition system. It has been concluded from the findings that chatter is the outcome of resonance, which occurs in the system when the frequency of secondary or primary serrated teeth formation is approximately equal to or an integer multiple of the ‘prominent mode frequencies’ of the system components.

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Tool condition monitoring in an end-milling operation based on the vibration signal collected through a microcontroller-based data acquisition system

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-007-1186-6 ◽

2007 ◽

Vol 39 (1-2) ◽

pp. 118-128 ◽

Cited By ~ 49

Author(s):

Julie Z. Zhang ◽

Joseph C. Chen

Keyword(s):

Data Acquisition ◽

Condition Monitoring ◽

End Milling ◽

Vibration Signal ◽

Data Acquisition System ◽

Tool Condition Monitoring ◽

Acquisition System ◽

Tool Condition ◽

Milling Operation

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Influence of Cutting Parameters on Chatter and Tool Wear During End Milling of Stainless Steel Conducted on VMC

IIUM Engineering Journal ◽

10.31436/iiumej.v3i2.361 ◽

1970 ◽

Vol 3 (2) ◽

Author(s):

A.K.M.N. AMIN, M. IMRAN AND M. ARIF

Keyword(s):

Stainless Steel ◽

Tool Wear ◽

Surface Finish ◽

End Milling ◽

Cutting Speed ◽

Cutting Parameters ◽

Wear Intensity ◽

Depth Of Cut ◽

Machined Surface ◽

Milling Operation

Stainless steels are a group of difficult to machine work materials. The difficulty in machining stainless steels is manifested in high contact length and stresses, formation of serrated chips and development of chatter resulting in high tool wear rates and poor machined surface finish. The paper focuses on the performance of TiN coated-carbide inserts in machining stainless steel specimens in end milling operation performed on vertical machining centre (VMC). The performance of the tool is evaluated from the point of view of its wear intensity, mechanism of failure and generation and effect of chatter on tool wear and vice versa. The investigations were aimed at determining the effect of cutting parameters, specifically cutting speed, feed and depth of cut, on chatter amplitude, tool wear rate, mechanism of tool wear and using these data and machined surface roughness values from previous work to come up with recommended values of cutting parameters for semi-finish and finish end milling operation of stainless steel work materials. For recording vibration signals a dual channel portable signal analyzers was used and the signals were analyzed using Pulse Multi-analyzer version 4.2 software. Tool wear was measured using an optical microscope with digital readout capabilities along 3 axes. The tool wear mechanisms were studied under a scanning electron microscope (SEM). Results of the investigation show that acceleration amplitudes generally increase with cutting speed and the magnitude of tool flank wears. It has been also found that an increase in feed and depth of cut leads to higher acceleration amplitudes. The most common wear mechanisms observed during machining of stainless steel are attrition, micro and macro chipping of the tool at lower cutting speeds, and diffusion and mechanical failures due to intensive chatter at higher speeds. It has been also established that stable cutting speeds with relatively low tool wear intensity and satisfactory machined surface finish can be achieved through proper selection of cutting parameters. A table of recommended cutting conditions has been developed for almost chatter free machining with low tool wear intensity and satisfactory surface finish. Key Words: Vertical Machining Centre, Machinability, Chatter, Cutting, Tool life.

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Experimental Investigations of AISI 410 and AISI 420 Martensitic Stainless Steel in CNC Dry Milling Operation

International Review of Mechanical Engineering (IREME) ◽

10.15866/ireme.v15i5.20055 ◽

2021 ◽

Vol 15 (5) ◽

pp. 237

Author(s):

Pramod George ◽

Philip Selvaraj D.

Keyword(s):

Stainless Steel ◽

Martensitic Stainless Steel ◽

Experimental Investigations ◽

Dry Milling ◽

Aisi 420 ◽

Milling Operation

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Everyday Products

10.1093/oso/9780198804079.003.0012 ◽

2017 ◽

Author(s):

David Segal

Keyword(s):

Stainless Steel ◽

Hard Candy

Chapter 12 describes material aspects of everyday products. For example, the role of nanoparticles in sunscreens. It also covers surfactants and their role in micelles in washing-up liquids. The role of nanotechnology in cosmetics is stressed. The surprising use of hydrogels in disposable nappies (diapers) and the role of microstructure in sweets such as hard candy (boiled sweets) are described. Other everyday products include breathable garments, stainless steel and acrylic textiles.

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