Skip to main content
Heritage Science

Table 6 Vickers microhardness (HV0.3) and microstructural features measured by image analysis: for coarse IMPs, maximum Feret diameter (dmax) and 90th percentile Feret diameter (d90) are reported both for elongated (with circularity f2 < 0.8) and rounded (f2 < 0.8) particles

From: Corrosion of aircraft heritage: a comparison between modern and historic Duralumin alloys

 

Sample

HV0.3

Plane

Grain size, µm

 

Coarse Intermetallics

Length (L)

Width (W)

L/W

Area %

Density (IMPs/mm2)

Circularity < 0.8 (elongated)

Circularity ≥ 0.8 (rounded)

dmax, µm

d90, µm

dmax, µm

d90, µm

P

P-1(p)

136 ± 8

PL0

222 ± 89

116 ± 36

1.9

2.2 ± 0.5

5479 ± 1228

18 ± 2

10.0 ± 0.4

7.5 ± 1.3

3.4 ± 0.2

PL1

186 ± 59

56 ± 14

3.3

2.3 ± 0.2

8192 ± 393

22 ± 2

8.9 ± 0.5

7.0 ± 1.4

2.9 ± 0.1

PL2

409 ± 24

43 ± 3

9.5

2.3 ± 0.1

6489 ± 603

17 ± 2

8.8 ± 0.9

6.7 ± 0.9

3.4 ± 0.2

P-1(s)

138 ± 10

PL0

206 ± 17

67 ± 15

3.1

3.1 ± 1.2

5522 ± 916

31 ± 7

14.0 ± 5.0

8.0 ± 2.0

2.8 ± 0.6

PL1

186 ± 8

78 ± 6

2.4

2.5 ± 0.1

7407 ± 206

27 ± 2

10.2 ± 0.6

6.1 ± 0.2

2.9 ± 0.1

PL2

209 ± 38

60 ± 6

3.5

2.3 ± 0.3

6252 ± 627

28 ± 3

10.4 ± 0.2

7.1 ± 0.9

2.7 ± 0.2

P-2(p)

140 ± 10

PL0

80 ± 13

66 ± 2

1.2

2.1 ± 0.1

5600 ± 286

16 ± 4

6.9 ± 0.4

5.3 ± 0.7

3.1 ± 0.1

PL1

131 ± 29

56 ± 8

2.3

2.1 ± 0.2

6478 ± 352

14 ± 2

7.9 ± 0.5

5.9 ± 0.3

3.3 ± 0.2

PL2

117 ± 19

46 ± 8

2.5

1.9 ± 0.1

6297 ± 71

14 ± 2

6.9 ± 0.2

7.9 ± 1.5

3.4 ± 0.1

P-3(p)

141 ± 11

PL0

78 ± 24

70 ± 6

1.1

1.9 ± 0.1

4961 ± 743

15 ± 2

9.7 ± 1.0

9.1 ± 0.9

3.3 ± 0.5

PL1

126 ± 25

33 ± 5

3.8

2.1 ± 0.3

6812 ± 1737

15 ± 2

8.3 ± 0.5

7.0 ± 0.3

3.2 ± 0.3

PL2

120 ± 15

39 ± 5

3.1

2.1 ± 0.1

6099 ± 1056

16 ± 2

9.4 ± 0.2

6.9 ± 1.4

3.2 ± 0.3

B

B(p)

130 ± 2

PL0

30 ± 3

26 ± 2

1.1

2.6 ± 0.3

7778 ± 610

17 ± 4

8.0 ± 1.0

5.7 ± 1.1

2.0 ± 0.2

PL1

46 ± 10

13 ± 1

3.5

2.7 ± 0.2

11872 ± 1113

14 ± 4

6.8 ± 0.5

4.7 ± 0.6

1.9 ± 0.1

PL2

34 ± 4

14 ± 1

2.4

2.6 ± 0.2

11846 ± 1425

13 ± 2

6.2 ± 0.2

5.1 ± 0.8

2.1 ± 0.1

B(s)

152 ± 1

PL0

216 ± 37

12 ± 1

18.0

2.4 ± 0.1

2479 ± 1615

11 ± 2

3.7 ± 0.2

3.7 ± 0.7

1.9 ± 0.1

PL1

160 ± 33

10 ± 1

16.0

2.7 ± 0.1

33599 ± 3398

11 ± 1

3.7 ± 0.1

3.3 ± 0.4

1.7 ± 0.1

PL2

119 ± 19

15 ± 2

7.9

2.7 ± 0.1

3997 ± 3548

8 ± 1

3.8 ± 0.3

3.3 ± 0.3

1.7 ± 0.1

Modern alloys

2024(p)

147 ± 9

PL0

64 ± 18

67 ± 12

0.9

1.8 ± 0.2

7694 ± 827

22 ± 6

9.1 ± 0.3

6.0 ± 3.0

2.0 ± 0.1

PL1

121 ± 26

50 ± 7

2.4

1.2 ± 0.2

5380 ± 980

16 ± 3

8.1 ± 0.2

4.8 ± 0.7

2.1 ± 0.3

PL2

113 ± 12

39 ± 2

2.9

1.2 ± 0.4

3573 ± 1049

24 ± 5

7.8 ± 0.5

5.4 ± 0.6

2.4 ± 0.1

2024(s)

145 ± 16

PL0

144 ± 26

68 ± 21

2.1

1.6 ± 0.3

8606 ± 1478

17 ± 2

5.6 ± 0.4

4.1 ± 0.5

2.2 ± 0.2

PL1

171 ± 17

19 ± 1

9.0

1.1 ± 0.1

8160 ± 1048

14 ± 1

5.4 ± 0.3

3.8 ± 0.6

2.0 ± 0.1

PL2

104 ± 116

40 ± 22

2.6

1.1 ± 0.2

8915 ± 1575

10 ± 1

5.0 ± 0.1

3.6 ± 0.1

2.0 ± 0.1

2017A(p)

122 ± 12

PL0

49 ± 11

45 ± 9

1.1

1.9 ± 0.3

7655 ± 118

14 ± 2

7.3 ± 0.1

8.0 ± 1.0

2.8 ± 0.1

PL1

56 ± 10

33 ± 2

1.7

2.0 ± 0.2

11287 ± 113

16 ± 3

7.1 ± 0.1

8.0 ± 2.0

2.0 ± 0.1

PL2

88 ± 17

31 ± 2

2.8

2.0 ± 0.1

11951 ± 272

16 ± 3

7.9 ± 0.5

8.0 ± 2.0

2.1 ± 0.2

Back to article page