Materials of die casting machine include structural steel, tool steel, and aluminum or copper alloys for durability and precision.

Today’s factories rely heavily on die casting machines. These powerful tools make all sorts of metal parts quickly and accurately. But what keeps them running smoothly for years? It comes down to the materials they’re built with.

The metals and alloys chosen affect everything – how well the machine performs, how long it lasts, and the quality of parts it produces.

In this article, we’ll look at the materials engineers pick for these machines and explain why those choices matter.

Core components and material functions of die-casting machines

Die-casting machines are high-precision systems for metal forming, and the choice of materials directly affects the life of the equipment and the quality of castings. According to the international die-casting standard (NADCA), the main components and material functions are as follows:

Component	Core function	Key material requirements
Die-casting mold	Metal forming cavity	High temperature resistance (>600℃), thermal fatigue resistance
Injection system	High-speed injection of molten metal	Wear resistance, metal corrosion resistance
Mold clamping mechanism	Ten thousand-ton clamping force maintenance	Creep resistance, structural stability
Hydraulic system	Power transmission and control	High pressure resistance (>30MPa), fatigue resistance
Fuse frame	Overall support and vibration buffer	High rigidity, damping characteristics
Safety protection	Operational safety guarantee	Impact resistance, flame retardancy

Die-casting mold core component materials

Mold core material

• Hot working die steel: H13 (American standard)/SKD61 (Japanese standard)/8407 (Swedish) is the mainstream, accounting for 75% of global mold materials.
• Features:
  • Heat resistance: high temperature hardness maintains HRC45+ (＞550℃)
  • Resistant to thermal fatigue: thermal conductivity ＞30W/m·K, reducing the risk of cracks
• Innovative materials: tungsten-molybdenum-based alloys (such as W302) are used for ultra-high temperature copper alloy die casting, and the service life is increased by 300%

Mold frame material

• Ductile iron QT600 (low-cost solution) or S50C medium carbon steel (high-precision scenario)

Key materials for hydraulic systems

• Cylinder: Aerospace-grade aluminum alloy (such as 7075-T6) to achieve lightweight, with a specific strength three times that of steel
• Seals: Polytetrafluoroethylene (PTFE) composite ceramic fiber, temperature resistance > 300°C

Materials of die casting machine

Structural Steel

Structural steel is one of the most commonly used and core materials for manufacturing die-casting machines. Engineers choose it mainly because of its high strength and rigidity. When the die-casting machine is working, the internal parts are very heavy, and the entire machine has to withstand the huge pressure during the casting process. Structural steel can just hold these heavy parts steadily and withstand these high pressures. So you see, the most critical parts of the die-casting machine, such as the skeleton frame of the entire machine and the template plate that fixes the mold, are all made of structural steel. Only in this way can the machine be stable enough and durable.

High-Grade Tool Steel

The manufacturing of die casting machine molds is inseparable from high-quality tool steel. Since the molds are in harsh working conditions of high temperature and high pressure for a long time, the materials we choose must be able to effectively resist deformation and wear. Tool steel is used because it has high hardness, excellent wear resistance and stable thermal properties. These characteristics ensure the precision and durability of the mold.

Aluminum Alloys

In the field of die-casting machine processing, aluminum alloy is our most commonly used casting material. This material combines the characteristics of durability and lightness, and has excellent heat dissipation performance – these characteristics make it particularly good at producing parts with complex structures and thin walls. In actual operation, it is also found that aluminum alloy is easy to process and easy to adjust in the later stage of machine repair. What’s more worth mentioning is that it is not easy to rust by nature, and this advantage is directly related to the service life of the equipment.

Copper Alloys

In die casting machine production, we will select copper alloy materials such as brass and bronze according to actual needs. Such materials are particularly suitable for scenarios that require efficient heat dissipation and wear resistance, so they are often used in key components such as nozzles and cores – they must continue to maintain dimensional accuracy under high temperature and high pressure environments.

Composite Materials

Composite materials such as carbon fiber reinforced plastic (CFRP) are increasingly being used in the manufacture of specific parts for die casting machines. These materials are characterized by high strength and low weight, which can produce parts that reduce the burden on the equipment while maintaining sufficient durability. Composite materials are particularly suitable for critical parts that require precise dimensions and are not easy to deform.

HAICHEN’s material innovation practice suggestions

Mold material upgrade path:

• Phase I: Promote Y10 steel to replace 3Cr2W8V, with a 200% increase in lifespan at the same cost
• Phase II: Layout gradient materials (FGMs), ceramic reinforcement layer (Al₂O₃+40%) for the cavity surface

Hydraulic system cost reduction strategy:

Key valve bodies use powder metallurgy steel (Densimet®), and the wear rate is reduced to 0.001mm/thousand times

In the manufacturing process of die-casting machines, we are extremely cautious in the selection of materials, which is directly related to whether the equipment can operate stably for a long time, maintain excellent performance and meet quality standards.

Structural steel provides basic support for the machine, high-grade tool steel ensures the wear resistance of key components, aluminum alloy takes into account both lightweight and heat dissipation characteristics, copper alloy performs well in electrical and thermal conductivity scenarios, and composite materials supplement specific functional requirements.

The scientific combination of these materials jointly guarantees the reliability and service life of the die-casting machine.