|
Item
|
National standard steel shot
|
High quality steel shot
|
|
Chemical composition%
|
C
|
0.85-1.20
|
0.10-0.20
|
|
Si
|
0.40-1.20
|
0.10-0.35
|
|
Mn
|
0.60-1.20
|
0.35-1.50
|
|
S
|
<0.05
|
<0.05
|
|
P
|
<0.05
|
<0.05
|
|
hardness
|
steel shot
|
HRC40-50
HRC55-62
|
HRC42-48
HRC48-54
|
|
density
|
steel shot
|
≥7.20 g/cm3
|
7.4g/cm3
|
|
metallographic structure
|
Tempered martensite or troostite
|
tempered martensite + bainite
|
|
appearance
|
round
hollow grain﹤10%
crack<15%
|
round
hollow grain﹤5％
crack <10%
|
