Crack Paths 2006

1808

Max.: 17.9

grains.

689 grains. Max.: 52.3

Levels

50

original

35

crack

crack

25

20

direction

15

measured

10

zone

5

1

M

= 45°

2

M

1

(a)

(b)

(c)

I

Figure 4. M2 = 45° sections of the ODFscomputed from individual grain orientations in steel A. (a) Along

crack paths. (b) Immediately ahead of crack tips (along the original crack direction) as shown in (c).

1b

1

1a

(a)

(b)

(c)

Figure 5. Twointeracting cracks in steel A. (a) S E Mmicrograph. (b) EBSDpattern quality map. (c) Grain

average misorientation spread distribution. In (b) and (c), strain increases with the darkness of the gray scale.

30

111

001

11101

4

2

SA-II

SA-I

001

A 101

001

11101

C

AC B

A

25

N D

9

6

(deg. )

Poles

B

B

A

C

{011}

11

10

20

{123}

5

is o r ie n t a t io n

{112}

001

101

SP-I

SP-II

C

1

{111}

105

7

B A

12

8

B

A

C

C

Point-to-point

T D

B

B

B

3

Point-to-origin

M

A

A

C

5

SA-II

SA-I

C

0

0

2

4

6

8

10

12

Distance (Pm)

(b)

(c)

(a)

Figure 6. Lattice reorientation by plastic deformation. (a) Misorientation profile along line A-C. (b) Poles of

the active slip systems at points A, B and C (relative to the shear stress axes). (c) Key for grain identification.