STEEL GRADES
ALLOY CAST STEEL
Alloy Cast Steel rolls have a lower carbon content range than Steel Base qualities. The matrix can be heat treated to give either a spheroidised pearlite, which gives an alloy of maximum toughness, or a fine pearlite for additional wear resistance. There are also small areas of primary carbide (hype reutectoid) which enhance wear resistance. However, the most important characteristic of this type of roll is its high strength and toughness, and therefore it is primarily used in roughing and semiroughing applications.
SPECIFICATIONS
Production Type Static Monobloc Cast Materials
Chemical C 0.8-1.4 | Si 0.2-0.6 | Mn 0.5-1.8 | P ≤0.05 | S ≤0.05 | Ni ≤1.0 | Cr 0.45-1.20 | Mo 0.2-0.45
Hardness 35-50 HSc | Tensile ≥ 650-740 Mpa | Bending ≥ 700-1100 Mpa
ADAMITE STEEL BASE
Adamite Steel Base rolls can be classified as high carbon alloy steel rolls. The carbon content is in the range 1.3-2.2% and alloy additions produce a structure containing no free carbon and a discontinuous hypereutectic carbide phase. However, for an increase in carbide there will be a reduction in toughness. The semi-continuous hypereutectic carbide in the microstructure will markedly increase the wear resistance of the material. Appropriate heat treatment gives this roll an excellent combination of hardness and strength, and the uniform hardness throughout the roll is ideal for deep, heavy sections.
SPECIFICATIONS
Production Type Static Monobloc Cast Materials
Chemical C 1.8-2.2 | Si 0.3-0.6 | Mn 0.7-1.1 | P ≤0.05 | S ≤0.05 | Ni ≤1.0 | Cr ≤ 2.0 | Mo ≤ 0.2
Hardness 40-50 HSc | Tensile ≥ 450-500 Mpa | Bending ≥ 508-755 Mpa
GRAPHITIC STEEL
Graphitic Steel roll is the inclusion of spheroidal type graphite in a pearlitic, steel-like matrix. Consequently, it can be classified between nodular cast iron and hypereutectoid cast steel. This free graphite in the microstructure gives “iron-like” roll finish and increases the roll bite. This graphite permits self-lubrication to reduce side wear and also dissipates heat to reduce thermal cracking. With excellent penetration of hardness, this quality is suitable for all types of section mills.
SPECIFICATIONS
Production Type Static Monobloc Cast Materials
Chemical C 1.3-1.5 | Si 1.2-2.0 | Mn 0.8-1.1 | P – | S – | Ni 0.6-1.3 | Cr 0.2-0.8 | Mo 0.2-0.6
Hardness 35-50 HSc | Tensile ≥ 390-490 Mpa | Bending ≥ 490-686 Mpa
