1. 6061-T6
Effects of Tool Size on Fracture and
Fatigue Behaviors of Friction Stir Spot
Welds of 6061-T6 Aluminum Sheets

2. 6061-T6
T1 T2 T3
T1 T2
T3 T3
T1 T2
T3
SEM
: 6061-T6
I

3. Abstract
Effects of tool size on fracture and fatigue behaviors of friction stir spot
welds (FSSW) in cross-tensile specimens of 6061-T6 aluminum sheets were
investigated based on experimental observations. Welds made by three tools
with different sizes, T1, T2 and T3, at different rotational speed, dwelling time
and indentation depth were tested under quasi-static opending conditions. The
nugget pullout, interfacial and mixed type failure modes can be observed.
The experimental results indicate that the failure strengths and failure modes of
good welds made under different processing conditions show significant
dependence on the tool size. Then, welds made by the three tools at the
optimum processing parameters of T3 tool were tested under cyclic opening
conditions. Under cyclic loading conditions, the fatigue lives and failure
modes of the welds strongly depend on the tool size and applied load amplitude.
For T1 tool, the mixed mode failure mode can be found. For T2 tool, when the
welds are subjected to high and low cycle fatigue loading conditions, the
upper-sheet and lower-sheet nugget pullout failure modes can be found,
respectively. For T3 tool, except the two failure modes mentioned above,
another transient failure mode can be found between them. Finally, optical and
scanning electron micrographs of the welds made by the three tools before and
after failure were examined and micro indentation tests of these welds were
conducted.
Keywords : aluminum 6061-T6, friction stir spot weld, tool size, fracture,
fatigue, failure mode
II

4. ................................................................................................................I
ABSTRACT ......................................................................................................... II
..................................................................................................................... III
.................................................................................................................VI
............................................................................................................... VII
......................................................................................................... 1
1-1 ............................................................................................................. 1
1-2 ......................................................................................... 3
................................................................................................. 4
2-1 6061-T6 ................................................................. 4
2-2 ..................................................................................... 5
2-2-1 .................................................................. 6
2-2-2 .......................................................... 7
2-2-3 .................................................................. 7
2-2-4 .......................................................................... 9
2-3 ................................................................................... 12
2-3-1 .................................................................................... 12
2-3-2 .................................................................... 12
2-3-3 - ................................................................................... 13
2-3-4 ................................................................ 14
................................................................................... 17
3-1 ................................................................................................... 17
III

5. 3-1-1 ............................................................................................ 17
3-1-2 ............................................................................ 17
3-1-3 ............................................................................ 18
3-1-4 .................................................................... 19
3-1-5 ........................................................................................ 19
3-1-6 (Design of Experiment, DOE) ............................................ 20
3-2 ................................................................................... 33
3-3 .................................................................. 36
3-4 ................................................................................................... 37
3-4-1 ............................................................................................ 37
3-4-2 ............................................................................ 37
3-4-3 EDS ..................................................................... 38
3-4-4 ........................................................................................ 38
3-4-5 ............................................................................................ 38
................................................................... 44
4-1 ................................................................................................... 44
4-2 ............................................... 47
4-3 ........................... 49
4-3-1 T3 ............................... 49
4-3-2 T3 SEM ...................... 50
4-3-3 T1 T2 T3 .............. 50
4-4 .................................................................. 56
4-5 ................................................... 60
4-6 ............................... 72
4-7 ........................... 80
4-8 SEM ........................... 86
IV

6. ........................................................................... 89
5-1 ................................................................................................... 89
5-2 ............................... 93
5-3 ........................... 99
5-4 SEM ......................... 108
..................................................................................................... 116
........................................................................................................... 118
V

7. 3-1 6061-T6 ........................................................... 23
3-2 .......................................................................................... 23
3-3 L 9 (34) ............................................................................................ 23
3-4 .............................................................................................. 39
3-5 .............................................................................................. 39
4-1 T3 ................................................ 45
VI

8. 2-1 [7]................................................................. 10
2-2 (A) (B) .......................... 10
2-3 ............................................................. 11
2-4 ................................................................. 14
2-5 .............................................................................. 15
2-6 .............................................................................. 15
2-7 ...................................................................................... 15
2-8 - .................................................................................... 16
3-1 .......................................................................... 24
3-2 .......................................................................................... 24
3-3 ...................................................................................... 25
3-4 .......................................................................... 25
3-5 .................................................................................. 26
3-6 ................................. 26
3-7 .......................................................................... 28
3-8 ......................................................... 29
3-9 ..................................................................... 30
3-10 ............................................................................................ 31
3-11 ................................................................................ 32
3-12 ................................................................... 32
VII

9. 3-13 ............................................................................................ 35
3-14 ........................................................... 40
3-15 EDS ............................................................ 41
3-16 ........................................................................................ 41
3-17 .................................................................................... 42
3-18 (MTS)......................................................................... 42
3-19 ........................................................................ 43
4-1 T3 ........................................................................ 46
4-2 T1 ........................................................ 48
4-3 T3 ........................................ 52
4-4 T3 ............ 53
4-5 T1 T3 .................................. 54
4-6 T1 T3 .................. 55
4-7 T3 ............................................ 57
4-8 T2 ............................................ 58
4-9 T1 ............................................ 59
4-10 T1 ...... 65
4-11 T2 ...... 67
4-12 T3 ...... 69
4-13 T1 T2 T3
..................................................................................................................... 71
4-14 T1 .............................. 75
VIII

10. 4-15 T2 .............................. 75
4-16 T3 .............. 76
4-17 T3 1400RPM ........ 76
4-18 T3 2000RPM ........ 77
4-19 T3 0 .......... 77
4-20 T3 15 ........ 78
4-21 T3 1.6 MM .... 78
4-22 T3 1.9 MM .... 79
4-23 ............................................................... 82
4-24 T3 .................................................. 83
4-25 T3 .......................................... 84
4-26 T3 .......................................... 85
4-27 T1 SEM .................................................. 87
4-28 T3 SEM ...................... 88
4-29 T3 SEM ...................................... 88
4-30 T1 ...................................... 91
4-31 T2 ...................................... 91
4-32 T3 ...................................... 92
4-33 T1 T2 T3 ............. 92
4-34 T1 .............................. 96
4-35 T2 .............................. 96
4-36 T2 .............................. 97
IX

11. 4-37 T3 .............................. 97
4-38 T3 .............................. 98
4-39 T3 .............................. 98
4-40 ................................. 102
4-41 T1 ............................ 103
4-42 T2 ............................ 104
4-43 T2 ............................ 105
4-44 T3 ............................ 106
4-45 T3 ............................ 107
4-46 T1 SEM .................................... 111
4-47 T2 SEM .................................... 112
4-48 T2 SEM .................................... 113
4-49 T3 SEM .................................... 114
4-50 T3 SEM .................................... 115
X

12. 1-1
(resistance spot welding, RSW)
Lin [1]
Thornton [2]
KHI ( ) MAZDA ( )
(friction stir spot welds,
FSSW) [3,4]
(FSSW)
(RSW)
(1) (2) (3)
(4) (5) (6) (7)
(8) (9)
1

13. 2

14. 1-2
(lap-shear specimen)
6061-T6 (1mm)
(cross-tension specimen)
3

15. 2-1 6061-T6
(FCC)
[5] Al-Mg-Si
6061-T6 2.71 600 1539
2 79.6 cal/g
3-4
2
T6
6000 2000 7000
3C
4

16. 2-2
(friction stir spot welding, FSSW)
(The Welding Institute, TWI) 1991 (friction stir
welding, FSW)[6]
2-1 [7]
1. Plunge
2. Complete
3. Retract
2000
5000 6000 7000
[8]
(dynamic recrystallization, DRX)
5

17. [9] [10]
2-2-1
2-2 [11]
1.
2.
3.
4.
5.
6.
Tozaki [12]
Tran [13]
6

18. Lin Arul
[1,14]
Tozaki [15]
[16]
6061-T6
2-2-2
Wang Lee[17] (base
metal, BM) (thermal-mechanical affected zone, TMAZ)
(stir zone, SZ) 2-3 2-3
2-2-3
(porosity)
(crack) (integrity)
7

19. [18]
1.
2.
3.
4.
5.
6.
7.
:
1.
2.
[19]
8

20. 2-2-4
2004
RX-8 [20]
3C
9

21. 2-1 [7]
2-2 (a) (b)
10

22. Weld
Central
Hole
Upper
Lower
BM HAZ TMAZ HAZ BM
(TMAZ+SZ)
(base metal, BM)
(heat affected zone, HAZ)
(thermal-mechanical
HAZ SZ
affected zone, TMAZ)
(stir zone, SZ)
2-3
11

23. 2-3
(mechanical fatigue)
(creep-thermal fatigue)
2-3-1
2-4
a m R :
max min max min min
max min , a , m , R
2 2 max
a m
R
R 0.1
2-3-2
2-5
2-5
[21]
2-6
12

24. 2-6
2-6 1 2 3 4 5
2-7
2-3-3 -
( )
( )
(high-cycle fatigue) -
(stress-life approach) ( )
( )
- (S-N curve) 2-8(a)
-
a Nf -
10 3 106
(fatigue limit)
(endurance limit) e
-
2-8(b) 106 10 7
(fatigue strength) [21]
13

25. 2-3-4
[22] Lin
Tran [13] Uematsu [23]
2-4
14

26. 2-5
2-6
2-7
15

27. (a)
(b)
2-8 -
16

28. 3-1
3-1-1
1 mm 6061-T6 SAE
152 mm 50 mm (cross-tention
specimen) 3-1
3-1-2
CNC
FSW
5HP 3-1 3-2
1°
3-3
CNC
17

29. (1) 3000 rpm
2000 rpm 700~2000
rpm
(2)
(3)
(4)
3-1-3
T1 T2 T3
3-4
SKD11
SKD11
60HRc
3-5
1. (tool holder)
18

30. 2. (tool shoulder)
3. (tool pin)
3-6 1
1 2 2 D1
1.5 3 S1 S2
3-1-4
3-7(a)(b)
(S45C)
51 mm
1 mm 2 mm 10 mm 18.5 mm
101.6 mm 3-7(c)
152 mm 50 mm 8 mm
14 16 18
mm 3-8 3-9(a)
( ) 3-9(b)
3-1-5
19

31. ( NT-411)
3-10
0.1~999.9
/ DIP SWICH
ENCODER L:0~3V,
H:6~30V Relay
RESET RESET RESET RESET
3-11
4 mm
(Switching Frequency) 600 MHz
( )
3-1-6 (Design of Experiment, DOE)
3-12
L 9 (34)
(Orthogonal Arrays, OA, 3-3)
Minitab
1960
20

32. C. R. Rao 1947 [24]
(parameter design) [25,26]
1. /
(subsystems)
2. / (ideal function/response)
(input signal, M) (output response, y)
(ideal function) y = bM
b (sensitivity)
3. (signal and noise factor SN)
(signal levels and ranges) (noise factors)
(noise strategy)
4. (control factors and levels)
(orthogonal array)
3 L 9 (34)
3-3
5. (collect data)
6. (conduct data analysis) SN ratios / /
(response tables/graphs )
7. (confirmation run)
8.
1. (Main effects plot for means)
N x 1 , ..., x i
21

33. N
1
x xi
N i 1
2. (Main effects plot for StDevs)
n
1
s ( xi x)2
n 1i 1
3. (Main effects plot for SN ratio)
y2
SN 10 log( 2 )
s
22

34. 3-1 6061-T6
Si Fe Cu Mn Mg Cr Zn Ti
% 0.4-0.8 0.7 0.15-0.4 0.15 0.8-1.2 0.04-0.35 0.25 0.15
T6 ASTM (515-550°C)
(155-165°C)18hr
3-2
(mm) (mm) (mm)
T1 8 3 1.5
T2 10 4 1.5
T3 12 5 1.5
3-3 L 9 (34)
No. of Factor
Run A B C D
1 1 1 1 1
2 1 2 2 2
3 1 3 3 3
4 2 1 2 3
5 2 2 3 2
6 2 3 1 1
7 3 1 3 2
8 3 2 1 3
9 3 3 2 1
A B C D
23

35. 3-1
(a) (b) (c)
(d)
3-2
24

36. (a)X (b)Y
(c)Z
3-3
T1 T2 T3
0 0 0
(mm) 8 10 12
(mm) 3 4 5
(mm) 1.5 1.5 1.5
3-4
25

37. 3-5
3-6
26

38. (b)
(c)
27

39. (c)
3-7
28

40. 3-8
29

41. (a)
(b)
3-9
30

42. 3-10
31

43. 3-11
Value
Tool rotation speed
Holding time
Tool displacement
0 t Time
3-12
32

44. 3-2
1 mm 6061-T6
(DOE)
3-13
0.2 mm/s
(1)
(2) 10~15
(3)
(4)
(5)
(6)
(7) 5
(8) 36 152 mm 50 mm
(9)
(10)
27
SEM
33

45. 6061-T6
:
1.
2.
3. 6061-T6
:
(DOE )
1.
2.
3.
4.
NG
SEM
( ) ( )
34

46. 3-13
35

47. 3-3
(DOE)
T3
100
10
90 % 80 % 70 % 60 % 50 % 40 % 30
% 20 % R 0.1
5 Hz
P(proportional) I(integration) D(derivative)
F(feed forward)
(1). MTS
(2). MTS
(3).
(4).
(5).
(6).
(7).
SEM
36

48. 3-4
3-4-1
(EHOMA 3SR300) (BUEHLER
ISOMET2000) 3-14 (
)
8
15 2
(BUHLER
ECOMET6) #120 #240 #400 #600 #1000 #2000
1 m 0.3 m
(HF) (H 3 PO 4 )
3-4 6061-T6
3-4-2
Zeiss Axiotech 25HD
50 100 200 500 1000
Nikon Coolpix 990
37

49. 3-4-3 EDS
3-15
EDS ( S3500N)
3-4-4
(micro
vickers hardness) Matsuzawa MHT2 (
3-16) 10g 25g 100g 200g 300g 500g 1000g
0.01mm 100 400
200 g 400
15
(micro Vickers hardness)
3-4-5
(SHIMADZU
AG-I) 5 kN 10 kN 3-17
MTS
( 647 Hydraulic Wedge Grip) 100 kN / 22 kip
21 MPa / 3000 psi 3-18 3-19
MTS
38

50. 3-4
(ml)
HF(44%) 15
H 3 PO 4 (85%) 10
water 75
3-5
Load cell Styles Model 45 (Order Code AL116)
Range 5000 lb
Excitation 10 VDC
Static Overload Capacity ±300% F.S.
Bridge Resistance 350
Operating Temperature -65°F to 200°F
39

51. 3-14
40

52. 3-15 EDS
3-16
41

53. 3-17
3-18 (MTS)
42

54. 3-19
43

55. 4-1
T3
T3 T1
T2 T3
(DOE) T3
(1) 700 1350 2000 rpm (2) 1.7 1.8 1.9 mm
(3) 0 7 14 sec. (4)
0.2 mm/s 4-1
4 4-1 700 rpm
1.7 mm 0 sec
800 rpm 1.65 mm 1
sec. T1 T2 T3 1321
1701 2372N
44

56. 4-1 T3
(rpm) (mm) (sec)
1 700 1.7 0
2 700 1.8 7
3 700 1.9 14
4 1350 1.7 7
5 1350 1.8 14
6 1350 1.9 0
7 2000 1.7 14
8 2000 1.8 0
9 2000 1.9 7
45

57. (a)
(b) SN
4-1 T3
46

58. 4-2
4-2 T1 T3
4-2(a) T1 4-2(b)
4-2(c)
T2 T3
47

59. (a)
(b) (c)
4-2 T1
48

60. 4-3
T1 T2 T3
4-3-1 T3
4-3 T3
4-3(a) 4-3(c) 4-3(a)
I II III IV T3
(1) 800 rpm (2) 1.65 mm (3) 1 sec. 4-3(a)
2-3 (stir
zone)
(TMAZ)
(HAZ)
4-3(a)
49

61. Thornton
[2]
4-3(c) I (base metal)
II (thermal-mechanical
affected zone)
III (stir zone)
Lin [1] 4-3(c) IV
4-3-2 T3 SEM
4-6 T3
SEM 4-4(a) A B
4-4(b) A 500
2000
4-4(c) B 500
2000
4-3-3 T1 T2 T3
4-5 T3
50

62. 4-5 T2 T3
T1
T1 T2 T3
4-6 T1 T2 T3 T3
4-6
T1
T2 T1
T3
51

63. (a)
(c)
4-3 T3
800 rpm 1 1.65 mm
52

64. (a)
(b)
(c)
4-4 T3
53

65. 4-5 T1 T3
800 rpm 1 1.65 mm
54

66. 4-6 T1 T3
800 rpm 1 1.65 mm
55

67. 4-4
(BM) (HAZ)
(TMAZ) (SZ)
200 g
400 15
(micro Vickers hardness) 4-9
0.5 mm 1.5 mm
6061-T6 120 Hv
(HAZ) (TMAZ)
(SZ) 4-7 T3
85~90 Hv
4-8 4-9 T2 T1
T3
56

68. 4-7 T3
57

69. 4-8 T2
58

70. 4-9 T1
59

71. 4-5
DOE T3
800 rpm 1 sec. 1.65 mm
2372N T1 T2 T3
1321N 1701N
T3
3
T1
4-10(a) T1
1 sec. 1.65 mm 0.2 mm/sec.
400~2000 rpm
700~1000 rpm 1300~1400 N
700 rpm T3 800 rpm
T1 T1
T1
1400 rpm 700 rpm
2000 rpm
4-10(b) 800 rpm 1.65 mm 3 sec.
60

72. 1341 N 6sec.
15 sec.
T1
15
4-10(c) 800 rpm 1 sec. 1.65
mm 1.7 mm 1325N
1.6 mm
1.7 mm
1.9 mm
T2
4-11(a) T2
1 sec. 1.65 mm 0.2 mm/sec.
400~2000 rpm 700 rpm
1731 N T3 800
rpm T2 T2
T2
800 rpm
1400 rpm
1400 rpm
4-11(b) 800 rpm 1.65 mm 1 sec.
1700 N 2
14 sec.~15 sec.
61

73. 4-11(c) 800 rpm 1 sec. 1.65 mm
1700 N 1.6 mm
1620 N 1.7 mm ~ 1.9
mm
1.9 mm.
T3
4-12(a) T3
1 sec. 1.65 mm 0.2 mm/sec.
400~2000 rpm 800 rpm
2372 N 900 rpm
1000~1400 rpm
2000 rpm
4-12(b) 800 rpm 1.65 mm 1 sec.
2372 N 2
4-12(c) 800 rpm 1 sec. 1.65 mm
2372 N 1.6 mm
2078 N 1.7 mm ~ 1.9
mm
1.9 mm.
62

74. 4-13 T1 T2 T3
T3 800 rpm T1 T2 700 rpm
T1 T2 T3
T1 T2
T1 T2
1400 rpm~2000 rpm
T3 1 sec.
T2 T3
T1
T1 T1
T3 1.65 mm
T2
T3 T1
1.6~1.7 mm 1.8~1.9
mm
63

75. (a)
(b)
64

76. (c)
4-10 T1
65

77. (a)
(b)
66

78. (c)
4-11 T2
67

79. (a)
(b)
68

80. (c)
4-12 T3
69

81. (a)
(b)
70

82. (c)
4-13 T1 T2 T3
71

83. 4-6
T3
T1 T2 T3
T3
T1
4-14 6061-T6 T1 T3
4-14(a)
4-14(b) 4-14(c)
(nugget pullout failure mode)
T2
4-15 T2 T3
4-15(a) 4-15(b)
4-15(c)
T1
(nugget pullout failure mode)
T3
4-16 T3 4-16(a)
4-16(b) 4-16(c)
(nugget pullout failure mode)
72

84. 4-17 T3 1400 rpm
4-17(a) 4-17(b)
4-17(c)
(interface fracture) 4-18 T3
2000 rpm 4-18(a)
4-18(b) 4-18(c)
4-17(c) 4-18(c)
2000 rpm
(nugget pullout failure mode) 2000
rpm 1400 rpm
4-19 T3 0
4-19(a) 4-19(b)
4-19(c)
(nugget pullout failure mode) 4-20
T3 15 4-20(a)
4-20(b) 4-20(c)
4-19(c) 4-20(c)
0 15
4-10(b) 4-11(b) 4-12(b)
4-21 T3 1.6 mm
4-21(a) 4-21(b)
4-21(c)
73

85. (nugget pullout failure mode) 4-22
T3 1.9 mm 4-22(a)
4-22(b) 4-22(c)
4-21(c) 4-22(c)
1.6 mm 1.9 mm
4-10(c) 4-11(c) 4-12(c)
74

86. (a) (b)
(c)
4-14 T1
800 rpm 1 1.65 mm
(a) (b)
(c)
4-15 T2
800 rpm 1 1.65 mm
75

87. (a) (b)
(c)
4-16 T3
800 rpm 1 1.65 mm
(a) (b)
(c)
4-17 T3 1400rpm
76

88. (a) (b)
(c)
4-18 T3 2000rpm
(a) (b)
(c)
4-19 T3 0
77

89. (a) (b)
(c)
4-20 T3 15
(a) (b)
(c)
4-21 T3 1.6 mm
78

90. (a) (b)
(c)
4-22 T3 1.9 mm
79

91. 4-7
4-3
4-23 T1 T2 T3
4-23(a) 4-23(b) 4-23(c)
4-1
4-23
4-24 T3
4-24(a) 4-24(b) 4-24(c)
700 rpm 1400
rpm 2000 rpm
90
4-24(a) 4-24(b) 4-24(c)
4-24 4-12(a)
Tozaki
[14,27]
80

92. 4-25 T3
4-25(a) 0 sec
4-25(c)
4-25(b)
0 sec 12
sec
4-26 T3
4-26(a)
1.6 mm
4-26(b) (d)
1.7 mm 1.9 mm
81

93. (a) T1
(b) T2
(c) T3
4-23
800 rpm 1 1.65 mm
82

94. (a)
(b)
(c)
4-24 T3
83

95. (a)
(b)
(c)
4-25 T3
84

96. (a)
(b)
(c)
(d)
4-26 T3
85

97. 4-8 SEM
T1
4-27 T1 SEM
A
40
500
(Dimple)[28,29]
(necking)
B
40
500
T3
4-28 SEM
A 40
500
4-29 SEM
A 60
200 2000
86

98. 4-27 T1 SEM
87

99. 4-28 T3 SEM
4-29 T3 SEM
88

100. 5-1
T1
T1 T3 100
1349N
90% 80% 70% 60% 50% 40% 30% 20%
R 0.1 5 Hz
T2 T3
4-30 T1 T3
-
10 3
10 3 2 10 3
2 10 3 106
106
106
T2
4-31 T2 T3
-
10 4
89

101. 10 4 106
106
T3
4-32 T3 -
4-31
10 4
10 4 106
106
4-33 -
T2 T3
T1
2 10 3
10 5 T2
T3
90

102. 4-30 T1
4-31 T2
91

103. 4-32 T3
4-33 T1 T2 T3
92

104. 5-2
T1 T2 T3 T3
T1
4-34 T1
50% 16074 4-34(a)
4-34(b)
4-34(c)
(mixed failure mode)
40%~90% 50%
T1
T1 T3
4-2 4-10 T1 700rpm
3 sec.
T1
T2
4-35 T2
60% 10843 4-35(a)
4-35(b)
93

105. 4-35(c) 4-35(b)
(nugget pullout failure mode)
4-36 T2
40% 94366 4-36(a)
4-36(b)
4-36(c) 4-36(a)
4-36(b) (c)
4-36(c)
(nugget pullout failure mode)
4-35 4-36
(nugget pullout failure mode)
80%~60%
50%~30%
T3
4-37 T3
60% 11768 4-37(a)
4-37(b)
4-37(c) 4-37(b)
4-38 T3
50% 21458 4-38(a)
94

106. 4-38(b)
4-38(c) 4-38(a)
4-38(b)
4-38(b)
4-39 T3
40% 51981 4-39(a)
4-39(b)
4-39(c) 4-39(a)
4-39(b) (c)
4-39(c)
T3
80%~50%
50%
50%~30%
T1 T2 T3
(nugget
pullout failure mode) (mixed failure mode)
95

107. (a) (b)
(c)
4-34 T1
50%
(a) (b)
(c)
4-35 T2
60%
96

108. (a) (b)
(c)
4-36 T2
40%
(a) (b)
(c)
4-37 T3
60%
97

109. (a) (b)
(c)
4-38 T3
50%
(a) (b)
(c)
4-39 T3
40%
98

110. 5-3
T1
4-40
4-41 T1
( 4-40 A-A ) 60%
1766 4-41(a)
4-41(b) (c)
A-A B-B 4-41(d) (e) (f)
4-41(b) I II 4-41(c) III 4-41(d)
(e) 4-41(f) 4-41(e)
III 4-41(d) (e)
B-B
T2
4-42 T2 (
4-40 A-A ) 60%
10388 4-42(a)
4-42(b) (c) A-A
B-B 4-42(d) (e) (f) 4-42(b) I
II 4-42(c) III 4-42(d) (e)
4-42(f) 4-42(e) III
4-42(d) (e)
99

111. B-B
4-43 T2 (
4-40 A-A ) 40%
83019 4-43(a)
4-43(b) (c)
A-A B-B 4-43(d) (e) (f) 4-43(b)
I II 4-43(c) III 4-43(d)
4-43(e)
4-43(f) 4-43(e) III
4-43(d) (e)
4-43(d)
(e)
T3
4-44 T3 (
4-40 A-A ) 60%
12187 4-44(a)
100

112. 4-44(b) (c) A-A
B-B 4-44(d) (e) (f) 4-44(b) I
II 4-44(c) III 4-44(d)
4-44(e)
4-44(f) 4-44(e) III 4-44(d)
(e)
B-B
4-45 T3 (
4-40 A-A ) 40%
47632 4-45(a)
4-45(b) (c)
A-A B-B 4-45(d) (e) (f) 4-45(b)
I II 4-45(c) III 4-45(d) (e)
4-45(f) 4-45(e) III 4-45(d) (e)
4-45(d) (e)
101

113. 4-40
102

114. (a)
(b)A-A
(c) B-B
(d)A-A (e)A-A
(f)B-B
4-41 T1
60% 1400 cycles
103

115. (a)
(b) A-A
(c) B-B
(d) A-A (e) A-A
(f) B-B
4-42 T2
60% 8500 cycles
104

116. (a)
(b) A-A
(c) B-B
(d) A-A (e) A-A
(e) B-B
4-43 T2
40% 66500 cycles
105

117. (a)
(b) A-A
(c) B-B
(d) A-A (e) A-A
(f) B-B
4-44 T3
60% 10000 cycles
106

118. (a)
(b) A-A
(c) B-B
4
(d) A-A (f) A-A
(e) B-B
4-45 T3
40% 35000 cycles
107

119. 5-4 SEM
T1
4-46 T1 SEM
60% 1960 4-46(a)
4-46(b) A SEM
30 4-46(c)
5000
(fatigue striation)
4-46(d) B SEM 30
4-46(e) 1000
T2
4-47 T2 SEM
60% 10843 4-47(a)
4-47(b) A SEM
30 4-47(c)
2000
(fatigue striation)
4-47(d) B SEM 30
4-47(e) 300
108

120. T1 B
4-48 T2 SEM
40% 67408 4-48(a)
4-48(b)
A SEM 30
4-48(c) 2000
4-48(d) B SEM
30 4-48(e)
1000
T3
4-49 T3 SEM 60%
15639 cycles 4-49(a)
4-49(b) A SEM
30 4-49(c) 3000
4-49(d) B SEM 30
4-49(e) 500
T1 B
4-50 T3 SEM 40%
42605 cycles 4-50(a)
4-50(b) A SEM
109

121. 40 4-50(c)
1000
4-50(d) B SEM
40 4-50(e) 5000
110

122. (a)
(b) (c)
(d) (e)
4-46 T1 SEM
60%
111

123. (a)
(b) (c)
(d) (e)
4-47 T2 SEM
60%
112

124. (a)
(b) (c)
(d) (e)
4-48 T2 SEM
40%
113

125. (a)
(b) (c)
(d) (e)
4-49 T3 SEM
60%
114

126. (a)
(b) (c)
(d) (e)
4-50 T3 SEM
40%
115

127. 6061-T6
[16]
T1 T2 T3 T3
T1 T2 T3 T3
SEM
1. T3 :
(1) 800 rpm (2) 1.65 mm (3) 1 sec. (4)
0.2 mm/s
2. T1 T2 T3 T3
1321N 1701N 2372N
3.
4. T1 T2 T3
T3 > T2 > T1
5.
116

128. 80Hv
6. T1 T2 T3 T3
T1 (mixed failure
mode) T2
T3 T2
7. SEM
117

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