Material Properties

Metric Standard

Metric
Material

Nominal
Diameter

Proof
Load

Yield Strength

Ultimate Strength

Elongation

Reduction of Area

Core Hardness

 

Class

mm

MPa

MPa

MPa

Min. %

Min. %

Min.

Max.

 

3.6

 

180

190

330

25

 

B52

B99.5

No Grade Mark
No Grade Mark

4.6

5 thru 36

225

240

400

22

35

B67

B99.5

4.8

1.6 thru 16

310

340

420

14

 

B71

B99.5

4.8 Grade Mark

5.8

5 thru 24

380

420

520

10

 

B82

B99.5

5.8 Grade Mark

8.8

< 16

580

 

800

12

 

C22

C32

8.8 Grade Mark

8.8

> 16 (12 for structural bolting)

600

660

830

12

35

C23

C34

9.8

Applies only to < 16

650

 

900

10

 

C28

C37

9.8 Grade Mark

10.9

6 thru 36

830

940

1040

9

35

C32

C39

10.9 Grade Mark

12.9

1.6 thru 36

970

1100

1220

8

35

C39

C44

12.9 Grade Mark

 

Imperial Standard

Inch
Material

Nominal
Diameter

Proof
Load

Yield Strength

Ultimate Strength

Elongation

Reduction of Area

Core Hardness

 

Grade

in

Ksi

Ksi

Ksi

Min. %

Min. %

Min.

Max.

 

1

1/4 thru 1-1/2

33

36

60

18

35

B70

B100

No Grade Mark
No Grade Mark

2

1/4 thru 3/4

55

57

74

18

35

B80

B100

2

Over 3/4 to 1-1/2

33

36

60

18

35

B70

B100

4

1/4 thru 1-1/2

65

100

115

10

35

C22

C32

5

1/4 thru 1

85

92

120

14

35

C25

C34

3 grade marks

5

Over 1 to 1-1/2

74

81

105

14

35

C19

C30

7

1/4 thru 1-1/2

105

115

133

12

35

C28

C34

5 grade mark

8

1/4 thru 1-1/2

120

130

150

12

35

C33

C39

6 grade mark