General
Demands placed on plastic mould tooling are increasing. Such conditions require mould steel that possess a unique combination of toughness, corrosion resistance and the ability to reach uniform hardness levels throughout large cross sections. Uddeholm Mirrax ESR has proven to be the right choice for these applications. Uddeholm Mirrax ESR is a premium grade stainless tool steel with the following properties:

• excellent polishability

• high corrosion resistance

• excellent through-hardening properties

• good ductility and toughness

• good wear resistance

The combination of these properties provides a steel with outstanding production performance. The practical benefits of good corrosion resistance in a plastic mould can be summarized as follows:

• Lower mould maintenance costs: The surface of cavity impressions retain their original finish over an extended service life. Moulds stored or operated in humid conditions require no special protection.

• Lower production costs: Since cooling channels are less likely to be affected by corrosion (unlike conventional mould steel), heat transfer characteristics, and therefore cooling efficiency, are constant throughout the mould life, ensuring consistent cycle times.

These benefits, coupled with the high wear resistance of Uddeholm Mirrax ESR, offer the moulder low-maintenance, long-life moulds for the greatest overall tooling economy.

Note! Uddeholm Mirrax ESR is produced using the Electro-Slag-Remelting (ESR) technique. The result is a mould steel with a very low inclusion level providing excellent polishability characteristics.

Applications
Although Uddeholm Mirrax ESR is recommended for all types of moulds, its special properties make it particularly suitable for moulds with the following demands:

• Corrosion/staining resistance, i.e. for moulding of corrosive materials, e.g. PVC, acetates, and for moulds subjected to humid working/storage conditions.

• High surface finish, i.e. for the production of optical parts, such as camera and sunglass lenses, and for medical components, e.g. syringes, analysis vials etc..

• Toughness/ductility, i.e. for complex moulds

• Outstanding through-hardening characteristics i.e. high-hardenability, important for larger moulds.