C45 steel, also known as 1045 steel in the U.S. and similar to other grades like AISI 1045, is a medium-carbon steel commonly used for mechanical and engineering applications. When specifically used in the context of plastic moulds, it is often referred to as a "plastic mould steel" in some industries, although it is not as commonly associated with high-performance moulds compared to grades like H13 or P20. Hereïs a detailed description of C45 block plastic mould steel:
Composition
C45 steel typically contains:
- Carbon (C) 0.42% - 0.50%
- Manganese (Mn) 0.60% - 0.90%
- Silicon (Si) Up to 0.40%
- Phosphorus (P) Up to 0.035%
- Sulfur (S) Up to 0.035%
Properties
- Hardness Can be heat-treated to achieve hardness levels around 50-55 HRC (Rockwell Hardness Scale).
- Strength Offers good tensile strength, generally around 550-700 MPa (80-102 ksi) in its hardened state.
- Ductility Provides good machinability and moderate ductility, allowing it to be formed and machined with relative ease.
- Toughness It is tougher than higher-carbon steels, making it less prone to cracking under stress.
- Wear Resistance Has moderate wear resistance compared to other tool steels, which can be sufficient for some plastic moulding applications.
Applications
- Plastic Moulds Used for manufacturing plastic moulds in applications where extreme hardness and wear resistance are not as critical. Itïs often employed in less demanding moulding tasks or where cost considerations are important.
- Machinery Parts Suitable for components that require good machinability and strength, such as shafts, gears, and other mechanical parts.
- Engineering Components Used in various engineering applications where medium strength and machinability are needed.
Heat Treatment
C45 steel can be heat-treated to enhance its properties:
- Hardening Typically heated to around 820-850C (1508-1562F) and then quenched in water or oil.
- Tempering After hardening, tempered at around 200-300C (392-572F) to relieve stresses and achieve the desired hardness.
Advantages
- Cost-Effective Generally more affordable compared to high-performance tool steels.
- Good Machinability Easier to machine than some other tool steels, which can reduce manufacturing costs.
- Moderate Strength and Toughness Provides a balance of properties suitable for many applications.
Disadvantages
- Lower Wear Resistance Not as wear-resistant as specialized plastic mould steels like H13 or P20, making it less ideal for high-volume or high-abrasion moulding applications.
- Corrosion Resistance Requires surface treatments or coatings for enhanced resistance to corrosion.
Standards
C45 steel is often produced according to standards such as:
- DIN 17200 German standard for steel grades, including C45.
- EN 10083 European standard for heat-treatable steels, including C45.
In summary, C45 block plastic mould steel is a medium-carbon steel that offers a good balance of strength, machinability, and affordability. It is suitable for plastic moulds in less demanding applications but may not be the best choice for high-performance or high-abrasion environments where specialized tool steels are preferred.