Superplast® 350

Premium mould steel that meets or exceeds standards for grades W 1.2738HH.

Material properties
Prehardened steel for medium and very large – size moulds and tools with good machinability. Consistent texturing and polishing improved by very low sulphur content. Reliable repair welding and good thermal conductivity.

For which tools
Plastic injection mould cores and cavities, large – size moulds for bumpers, dashboards, fenders, television panels, bottle crates, etc.

For which plastics
Thermoplastics (PE, PP, PS), thermosetting plastics, ABS, transparent melts. Injection moulding, compression moulding, RIM moulding, etc.

Chemical analysis

Typical values (weight%).

C Si Mn S Ni Cr Mo B
0.26 0.10 1.50 0.002 0.30 1.60 0.65 +

Mechanical properties

Superplast® 350 is delivered quenched and tempered to 330 – 370 HB (35 – 39 HRC).

Hardness Rp 0.2 Yield strength Rm Tensile strength Elongation Reduction of area K C V 20°C Elastic modulus
HB MPa ksi MPa ksi % Z% J GPa ksi
345 940 136 1095 159 15 50 25 205 29733

Dimensional program

Typical delivery sizes

Manufacturing process Thickness Width
Hot rolling 15 – 150 mm 1000 – 2000 mm
Hot forging 150 – 1200 mm 1000 – 2000 mm

For more technical details :


Superplast® 350

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.