Davim Machining and Machine-tools

Research and Development
1. Auflage 2013
ISBN: 978-0-85709-219-9
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 280 Seiten

Reihe: Woodhead Publishing Reviews: Mechanical Engineering Series

This book is the third in the Woodhead Publishing Reviews: Mechanical Engineering Series, and includes high quality articles (full research articles, review articles and case studies) with a special emphasis on research and development in machining and machine-tools. Machining and machine tools is an important subject with application in several industries. Parts manufactured by other processes often require further operations before the product is ready for application. Traditional machining is the broad term used to describe removal of material from a work piece, and covers chip formation operations including: turning, milling, drilling and grinding. Recently the industrial utilization of non-traditional machining processes such as EDM (electrical discharge machining), LBM (laser-beam machining), AWJM (abrasive water jet machining) and USM (ultrasonic machining) has increased. The performance characteristics of machine tools and the significant development of existing and new processes, and machines, are considered. Nowadays, in Europe, USA, Japan and countries with emerging economies machine tools is a sector with great technological evolution. - Includes high quality articles (full research articles, review articles and cases studies) with a special emphasis on research and development in machining and machine-tools - Considers the performance characteristics of machine tools and the significant development of existing and new processes and machines - Contains subject matter which is significant for many important centres of research and universities worldwide

Autoren/Hrsg.

Davim, J. Paulo

Leseproben

List of figures and tables

Figures

1.1. Experimental set-up in a CNC lathe showing an AE sensor mounted on the tool holder (taken from Hu 2008) 7

1.2. AE-FFT intensity (high and low frequencies) with cutting time for insert F 9

1.3. AE-FFT at different time periods for insert F during the failure pass: (a) first, (b) second, (c) third and (d) last 25 per cent cutting time of the entire machining pass 10

1.4. AE-FFT amplitude comparisons in the four sub-periods during the coating failure pass of insert F 11

1.5. Illustration of the short-time Fourier transform (STFT) method (from Lu 2010) 12

1.6. Raw AE signal for insert A at: (a) initial cutting pass and (b) tool failure pass 13

1.7. AE-RMS amplitude during initial cutting and tool failure pass for insert A (from Lu 2009) 14

1.8. AE-RMS during tool failure pass: (a) with clear failure transition period (insert A) and (b) without clear failure period (insert B) (from Lu 2009) 15

1.9. FFT spectra of raw AE signals from two cutting passes of insert A: (a) initial cutting and (b) final cutting (from Lu 2009) 15

1.10. AE-FFT intensity of high- and low-frequency components with cutting time for (a) insert A and (b) insert B (from Lu 2009) 16

1.11. AE-FFT of insert A: (a) initial cutting pass and (b) coating failure pass 17

1.12. AE-FFT of insert B: (a) initial cutting pass and (b) coating failure pass (from Lu 2009) 17

1.13. AE-FFT at different time periods for insert A during the coating failure pass: (a) first, (b) second, (c) third and (d) last 25 per cent cutting of the entire pass (from Lu 2009) 18

1.14. AE-FFT amplitude comparisons, between the low- and high-frequency components, in the four sub-periods during the coating failure pass: (a) insert A and (b) insert B (from Lu 2009) 18

1.15. Amplitude ratio of the high/low-frequency components by the STFT method during different cutting passes of insert A: (a) initial cutting passes, (b) prior to failure pass and (c) failure pass (from Lu 2010) 20

1.16. Amplitude ratio of high/low-frequency components by the STFT method during coating failure passes of insert B (from Lu 2010) 20

1.17. Tool wear development of cutting inserts (A, B and C) with cutting time 21

1.18. Amplitude ratios of high/low-frequency components by the STFT method during coating failure pass for insert C (from Lu 2010) 22

1.19. Tool wear development of inserts D, E and F with cutting time (from Lu 2010) 23

1.20. Amplitude ratio of high/low-frequency components during the coating failure pass: (a) insert D, (b) insert E and (c) insert F (from Lu 2010) 24

2.1. World production of stainless steel in the last decade 31

2.2. Effect of alloy elements on AISI304 austenitic stainless steel 35

2.3. Photomicrographs of AISI303 (× 200) 45

2.4. Scheme of the experimental equipment 46

2.5. Directions of the three components of cutting force acquired by a Kistler 9121 dynamometer 46

2.6. Areas for roughness measurement in the machined specimen 47

2.7. (a) Equipment for image acquisition, and (b) software developed for tool wear measurement 48

2.8. Orthogonal cutting scheme 50

2.9. Comparison between simulated and experimental tangential forces over a wide range of cutting conditions 53

2.10. (a) Relationship between cutting force and cutting speed, and (b) normalized cutting forces 54

2.11. Relationship between shearing angle and cutting speed 54

2.12. Effect of cutting speed on tool temperature 55

2.13. Thermal energy by unit of volume with respect to 56

2.14. Relationship between temperature in the tool–chip interface and c 56

2.15. Plastic strain rate versus cutting speed (c) 57

2.16. Chip formation versus cutting speed (n = 0.1 mm/rev) 58

2.17. Chip thickness versus cutting speed 59

2.18. Effect of non-deformed chip thickness on specific cutting energy (s) 61

2.19. Relationship between cutting forces and feed rate 61

2.20. Probe, photomicrograph and micro-hardness measurement for AISI303 63

2.21. Relationship between tangential cutting force and cutting speed (n = 0.2 mm/rev; p = 1 mm) 64

2.22. Relationship between cutting force amplitude and cutting speed 67

2.23. Scanning electron micrographs of the machined surfaces at different cutting speeds 69

2.24. Relationship between chip thickness and cutting speed 70

2.25. Average microhardness values 71

2.26. Depth of deformed microstructure for specimens machined at different cutting speeds 72

2.27. SEM mapping image of adhered material in the tool flank face 73

2.28. EDX chemical composition analysis for new and worn cutting tools 74

2.29. Scanning electron micrographs showing tool flank wear at several cutting speeds 75–6

2.30. Scanning electron micrographs showing crater wear at several cutting speeds: (a) c = 37 m/min; (b) c = 450 m/min; (c) c = 870 m/min. (d) EDX analysis of areas A and B. 78–9

2.31. Micrograph of a chip for AISI303 stainless steel: (a)morphology of chip under orthogonal cutting with c = 60 m/min and n = 0.2 mm/rev; (b)portion of chip 81

2.32. Scanning electron micrographs of chips at several cutting speeds 82

2.33. Chip sliding surface at several cutting speeds 83–4

3.1. A pair of asymmetric rotors. (a) Schematic drawing, (b) finished parts. Left, male; right, female 96

3.2. Schematic of the workpiece holder assembly 98

3.3. Calibration scheme for radial forces and torque 99

3.4. Calibration curves for axial force and torque 101

3.5. Force trends as a function of the workpiece rotation angle, when the -axis of the sensor is oriented vertically: (a) experimental, (b) theoretical 101

3.6. Workpiece mounted in a grinding machine 102

3.7. Force components and torque during idle strokes without material removal 104

3.8. Trends of force components and torque as a function of the rotation angle of the workpiece: wheel speed = 32 m/s, feedrate = 1500 m/min, depth of cut = 0.05 mm 106

3.9. Trends of force components and torque as a function of the rotation angle of the workpiece: wheel speed = 32 m/s, feedrate = 3000 m/min, depth of cut = 0.1 mm 106

3.10. Trends of force components and torque as a function of the rotation angle of the workpiece: wheel speed = 38 m/s, feedrate = 3000 m/min, depth of cut = 0.1 mm 107

3.11. Main effects plot of the grinding parameters for torque 108

4.1. Wheel clogging 123

4.2. Grinding wheel with lodged chips (100 ×) 124

4.3. Effect of compressed air jet on wheel cleaning 127

5.1. Principle of the electric discharge machining process 141

5.2. Schematic of electric discharge machine 142

5.3. Conventional die sinking EDM 143

5.4. (a) Wire EDM,...