Material

C

Mn

Si

Cr

S

P

50Mn

0.48-0.56

0.70-1.0

0.17-0.37

≤0.25

≤0.035

≤0.035

60Mn

0.57-0.65

0.70-1.0

0.17-0.37

≤0.25

≤0.035

≤0.035

65Mn

0.60-0.70

0.90-1.2

0.17-0.37

≤0.25

≤0.035

≤0.035

B2

0.70-0.85

0.70-0.80

0.17-0.37

0.2-0.7

≤0.03

≤0.03

75SiMn

0.70-0.90

0.70-1.20

0.4-0.8

≤0.25

≤0.03

≤0.03

Wear-resistant Alloy

0.50-0.65

0.4-1.0

1.4-1.8

0.9-1.2

≤0.03

≤0.03

Material

Impact Test(Ak.J/cm²)

Endurance Test Times(5m/T)

Surface Hardness

(Φ25mm- Φ60mm)

Core Hardness

(Φ25mm- Φ60mm)

Surface Hardness

(Φ70mm- Φ100mm)

Core Hardness

(Φ70mm- Φ100mm)

Breakage

50Mn

≥12

≥10000

≥56

≥35

≥56

≥28

<1%

60Mn

≥13

≥10000

≥58

≥38

≥58

≥29

<1%

65Mn

≥15

≥12000

≥60

≥42

≥60

≥30

<1%

B2

≥17

≥12000

≥60

≥52

≥60

≥50

<1%

75SiMn

≥16

≥12000

≥60

≥50

≥60

≥48

<1%

Wear-resistant Alloy

≥17

≥12000

≥60

≥54

≥60

≥52

<1%

Norminal Diameter

Diametrical Tolerance(mm)

Approx Weight of Single Ball(kg)

Average Number of One MT

20mm/0.75''

+1,-0.5

0.033

30303

25mm/1''

+1,-0.5

0.064

15625

30mm/1.25''

+2,-1

0.11

9090

40mm/1.5''

+2,-1

0.261

3831

50mm/2''

+2,-1

0.51

1961

60mm/2.5''

+2,-1

0.883

1132

70mm/2.75''

+3,-1.5

1.402

713

80mm/3.25''

+3,-1.5

2.092

478

90mm/3.5

+3,-1.5

2.98

335

100mm/4''

+3,-1.5

4.087

244

110mm/4.5''

+3,-1.5

5.44

183

120mm/4.75''

+3,-1.5

7.062

141