Superplast® Premium

Superplast® Premium mould steels for high surface finish

Material properties
40 HRC pre-hardened grade designed for the plastic mold industry with stringent requirements.
High resistance to wear, high toughness, good polishing properties.
Thanks to a special solidification process, extreme low level of segregation are achieved even at mid-thickness. This grade is thus particularly indicated for high surface finish such as optical polishing (optics for automotive) or complex texturing (logos on dashboard).

For which applications
Plastic injection or compression mould cores and cavities with high quality finish, compression dies under high mechanical and thermal stresses.
Thermoplastics (PE, PS, PP), LFT, thermosetting plastics, ABS, transparent melts.

Chemical analysis

Typical values (weight%).

Hardness C Si Mn S Ni Cr Mo Add
345 0.26 0.10 1.50 0.002 0.30 1.60 0.65 B
370 0.25 0.10 1.15 0.002 0.75 2.00 0.60 B,V

Mechanical properties

Superplast® Premium is delivered quenched and tempered to 330 – 370 HB (35 – 39 HRC) or 350-380 HB (37-41 HRC).

Hardness Rp 0.2 Yield strength Rm Tensile strength Elongation Reduction of area KCV 20°C Elastic modulus
HB MPa ksi MPa ksi % Z% J GPa
345 940 136 1095 159 15 50 25 205
370 1000 145 1200 174 14.5 49 20 205

Typical values – thickness 400 mm – quenched and tempered


Thanks to a specific solidification process, Superplast® Premium steels exhibit a high homogeneity in both hardness and metallurgical structure (bainite + martensite) through the whole block, up to 600 mm thickness. This aims at improved and reproducible performances in polishing, texturing and global surface aspect.

Reliable texturing abilities

Thanks to the absence of segregation, texturing is not limited to easy patterns anymore. SP Premium is suitable for geometrical and other complicated patterns (logos for instance).


Superplast Premium can be polished up to SPI A2 (3-6µm, mirror polishing).
Apparition of orange peel or waves is limited thanks to the absence of segregation.

Dimensional program

Typical delivery sizes

Thickness Width
150-600 mm 1000-2000 mm


For more technical details :


Superplast® Premium

Download the complete datasheet

Technical data and information are to the best of our knowledge at the time of publication. However, they may be subjected to some slight variations due to our ongoing research programmes. Therefore, we suggest that information be verified at time of enquiry or order. Furthermore, in service, real conditions are specific for each application. The data presented here are for the purpose of description only, and can be considered as guarantees only when written formal approval has been provided by our company. Industeel reserves the right to change its product range at any time without prior notice.