Mold Steel 
1.2738 mould steel is no ordinary mould steel. It is a specially engineered, pre-hardened premium plastic mould steel. Its core value lies in:
‘Pre-hardened and ready to use’ – saving time and effort: The material undergoes precise tempering (pre-hardening) before leaving the factory, achieving an ideal hardness range of approximately HRC 30-36. This eliminates the need for complex and time-consuming quenching and tempering processes upon receipt, significantly shortening the mould manufacturing cycle. It also reduces the risk of heat treatment deformation, keeping project timelines firmly under control.
| Equivalent grades | GB | DIN | AISI | JIS | DAIDO | |||||
| 3Cr2MnNiMo | 1.2738 | P20+Ni | — | — | ||||||
| Chemical Composition | C | Si | Mn | Cr | P | S | Ni | Mo | W | Other |
| 0.35-0.48 | 0.20-0.40 | 1.30-1.60 | 1.80-2.10 | 0.03MAX | 0.03MAX | 0.90-1.20 | 0.15-0.25 | – | – | |
| Available size | Round Bar | Diameter | Length | |||||||
| 10-800mm | 2000-6000mm | |||||||||
| Flat Bar | Thickness | Width | Length | |||||||
| 16-1000mm | 200-2200mm | 2000-6000mm | ||||||||
| Surface condition | Black surface/ Grinded/ Machined | |||||||||
| Annealed hardness | 28-35 HCR (After tempering ) | |||||||||
| Characteristics | Good polishing and photo-etching properties Good machinability High purity and good homogeneity Uniform hardness | |||||||||
| Applications | Injection moulds for thermoplastics | |||||||||
| Extrusion dies for thermoplastics | ||||||||||
| Blow moulds | ||||||||||
| Forming tools, press – brake dies (possibly flame hardened or nitrided ) | ||||||||||
| Aluminium die casting prototype dies | ||||||||||
| Structural components, shafts . | ||||||||||
| Heat Treatment | Annealing | 710 – 730 °C | ||||||||
| Hardness after annealing | Max. 240 HB | |||||||||
| Stress relieving | Approx. 600 °C | |||||||||
| Hot forming | 1050 – 850 °C | |||||||||
| Hardening | 870 – 890 °C | |||||||||
| Quenching media | Oil, Salt bath, Vacuum | |||||||||
| Hardness after quenching | 50 – 54 HRC | |||||||||
| Hardness after tempering | 100 °C | 200 °C | 300 °C | 400°C | ||||||
| 52HRC | 51HRC | 49HRC | 46HRC | |||||||
Pure lineage, stable and reliable: Premium 1.2738 employs advanced smelting techniques (e.g., EAF+LF+VD), ensuring high purity and uniform, dense microstructure. This inherently endows it with outstanding toughness, dimensional stability, and exceptional polishing performance, fundamentally guaranteeing long mould life and consistent product quality.
All-round performer, balanced performance: In its pre-hardened state, it perfectly balances high toughness, excellent machinability (cutting, milling, EDM), outstanding polishing capability (achieving mirror-like A1 grade), and superb etching performance. This makes it the ideal choice for manufacturing high-quality plastic products with stringent requirements.
