Material Introduction:
The high-speed steel rolls are produced through a horizontal centrifugal composite casting process. The high-hardness high-speed steel working layer is metallurgically fused with the core spheroidal iron to form a composite roll. The high-speed steel material contains a large amount of alloy elements such as Mo, V, W, and Cr. The tempered martensite matrix structure is distributed with high-hardness eutectic carbides like MC, M2C, and M6C, as well as granular secondary carbides. Therefore, it has excellent high-temperature wear resistance and heat resistance. At the same time, the anti-surface roughness performance is also very good. Under hot rolling conditions, a wear-resistant oxide film is generated on the high-speed steel roll surface, which plays a good role in the friction characteristics and the surface quality of the strip material.
Chemical Composition:
|
Classification |
Roll body hardness HSD |
C |
Si |
Mn |
Ni |
Cr |
M0 |
V |
W |
|
High-speed steel (HSS) |
75〜95 |
1.5 / 2.0 |
0.3 / 1.0 |
0.4 / 1.2 |
0.0 / 1.5 |
3.0 / 8.0 |
2.0 / 8.0 |
2.0 / 9.0 |
0.0 / 8.0 |
|
Medium-speed steel S-HSS |
75〜95 |
0.6 / 1.2 |
0.8 / 1.5 |
0.5 / 1.0 |
0.2 / 1.2 |
3.0 / 9.0 |
2.0 / 5.0 |
0.4 / 3.0 |
0.0 / 3.0 |
Mechanical properties:
|
Attribute |
Roll body |
Roll neck |
|
Tensile strength (N/mm2) |
≥760 |
≥760 |
|
Bending strength (N/mm2) |
770〜1020 |
425〜500 |
Metallographic structure:
Tempered martensite + bainite + carbides
Application:
The working rolls of the roughing stand and the pre-finishing stand of the strip rolling machine, as well as the rolls of the cold rolling machine