Chemical Composition (%)

Grade

C

Si

Mn

P

S

Cr

Mo

Cu

Ni

V

Al

W

Nb

N

P11

0.05~0.15

0.5~1.0

0.3~0.6

≤ 0.03

≤ 0.03

1.0~1.5

0.5~1.0

P12

0.05~0.15

≤ 0.5

0.3~0.61

≤ 0.03

≤ 0.03

0.8~1.25

0.44~0.65

P22

0.05~0.15

≤ 0.5

0.3~0.6

≤ 0.03

≤ 0.03

1.9~2.6

0.87~1.13

P5

≤ 0.15

≤ 0.5

0.3~0.6

≤ 0.03

≤ 0.03

4.0~6.0

0.45~0.65

P91

0.08~0.12

0.2~0.5

0.3~0.6

≤ 0.02

≤ 0.01

8.0~9.5

0.85~1.05

≤ 0.4

0.18~0.25

≤ 0.015

0.06~0.10

0.03~0.07

P92

0.07~0.13

≤ 0.5

0.3~0.6

≤ 0.02

≤ 0.01

8.5~9.5

0.3~0.6

B0.001 0.006

≤ 0.4

0.15~0.25

≤ 0.015

1.5~2.0

0.04~0.09

0.03~0.07

Mechanical Properties

Grade

Tensile strength(MPa)

Yield strength(MPa)

Elongation(%)

Impact energy(J)

Hardness

P11

≥ 415

≥ 205

≥ 22

≥ 35

≤ 163HB

P12

≥ 415

≥ 220

≥ 22

≥ 35

≤ 163HB

P22

≥ 415

≥ 205

≥ 22

≥ 35

≤ 163HB

P5

≥ 415

≥ 205

≥ 22

≥ 35

≤ 187HB

P91

585~760

≥ 415

≥ 20

≥ 35

≤ 250HB

P92

≥ 620

≥ 440

≥ 20

≥ 35

250HB