What Die casting mould material we mainly using? Die casting moulds primarily use specialized hot-work tool steels that withstand extreme temperatures, high pressures, and repeated thermal cycling.

The most common grades include H13, SKD61, DAC55, 8407, and DIEVAR. Each material offers distinct properties that make it suitable for specific applications, from automotive engine blocks to electronic housings. Choosing the right mould material directly affects your tool life, part quality, and production cost.

This guide walks you through the main Die casting mould material, their key properties, and where manufacturers apply them in production.

H13 Tool Steel: The Industry Standard

What is H13 tool steel? H13 is a chromium-based hot-work tool steel that dominates the die casting industry. It contains approximately 5% chromium, 1% molybdenum, and 1% vanadium, which give it excellent heat resistance, toughness, and thermal fatigue resistance. H13 maintains stable strength at temperatures around 600°C, making it the go-to choice for most die casting applications.

Key properties of H13:

• Excellent thermal fatigue resistance—resists heat checking from repeated heating and cooling cycles
• Good toughness and ductility—hardness above 52 HRC
• High heat stability—maintains strength at elevated temperatures
• Widely available and well-understood—proven performance across industries

Where manufacturers apply H13:

Automotive parts. H13 produces dies for aluminum engine blocks, transmission housings, and gearbox components. The material withstands the high temperatures and pressures of aluminum die casting while maintaining dimensional stability over thousands of cycles. Major manufacturers use H13 for giga casting dies—massive moulds that produce large structural components for electric vehicles, with clamping pressures reaching 6,000 to 9,000 tons.

Aluminum, magnesium, and zinc die casting. H13 serves as the primary mould material for all three common die casting alloys. For aluminum casting, H13’s corrosion resistance matters because aluminum is significantly more chemically aggressive toward tool steel than zinc. For magnesium and zinc, H13 provides the thermal stability needed for consistent production.

Extrusion and forging tools. Beyond die casting, H13 finds use in extrusion dies for aluminum and brass, as well as forging dies, hot punching tools, and hot swaging dies.

Haichen’s approach to H13 moulds. Haichen Machinery recommends H13 Die casting mould material as the starting point for most die casting mould applications. We work with customers to select the right H13 grade based on their specific alloy and production volume. For standard production runs, Haichen’s technical team helps buyers verify material certification and heat treatment quality to ensure consistent mould performance across the entire production lifecycle.

SKD61: The Japanese Standard

What is SKD61? SKD61 is the Japanese Industrial Standard (JIS) equivalent of H13. It shares the same basic chemistry—0.4% carbon, 5.2% chromium, 1.3% molybdenum, and vanadium. Manufacturers widely use SKD61 across Asia, particularly in Japan, China, and Southeast Asia.

Key properties of SKD61:

• Equivalent performance to H13 in most applications
• Excellent heat resistance and fatigue resistance
• Well-established supply chain in Asian markets
• Service life typically 100,000-150,000 shots

Where manufacturers apply SKD61:

Automotive and motorcycle parts. SKD61 serves the same applications as H13—engine components, transmission parts, and structural elements.

Aluminium alloy cavity moulds. SKD61 works well for aluminum die casting applications where thermal conductivity and dimensional stability are critical.

Enhanced cooling channel designs. Manufacturers use SKD61 moulds with copper linings in cooling channels to improve cooling performance and extend mould life in high-pressure die casting applications.

Telecom and electrical parts. The material works well for precision components in telecommunications equipment and electrical appliances.

Haichen’s experience with SKD61. Haichen has extensive experience supplying die casting machines that work with SKD61 moulds. We help buyers understand the performance differences between SKD61 and premium grades, ensuring they select the right material for their production targets. Haichen’s technical team provides guidance on heat treatment parameters and maintenance practices that maximize SKD61 mould life.

DAC55: High-Performance Alternative

What is DAC55? DAC55 is a premium hot-work tool Die casting mould material steel that offers significantly higher toughness than standard SKD61. Its chemistry—5.2% chromium, 2.2% molybdenum, vanadium, and nickel—provides a balanced combination of toughness and strength.

Key properties of DAC55:

• Higher toughness than SKD61—enables higher initial hardness
• Better fatigue resistance—handles more cycles before failure
• Balanced strength and toughness—suits demanding applications
• Service life 1.4 times longer than SKD61
• Working temperature up to 600°C

Where manufacturers apply DAC55:

Automotive cylinder blocks and heads. The improved toughness makes DAC55 suitable for large, complex automotive castings where thermal stress is severe.

Large or squeeze die casting moulds. DAC55 delivers excellent heat crack resistance for large moulds and squeeze die casting applications.

High-performance die casting. The material retains DAC’s advantages while offering better heat crack resistance, making it suitable for demanding production environments.

Haichen’s recommendation for DAC55. Haichen recommends DAC55 when buyers need longer tool life than SKD61 but cannot justify the cost of even more premium grades. The 1.4x service life improvement translates into real cost savings over the life of the mould. Haichen’s engineers help buyers evaluate whether the higher upfront cost of DAC55 delivers a positive return on investment based on their specific production volume and alloy type.

Premium Grades: 8407 and DIEVAR

What are 8407 and DIEVAR? 8407 is a premium-grade tool steel known for superior thermal stability and high hardness. DIEVAR is a chromium-molybdenum-vanadium alloyed super alloy that offers optimized hardness-toughness balance. These premium smelted steels contain carefully balanced combinations of chromium, molybdenum, and vanadium to drastically delay heat checking.

Key advantages of premium grades:

• Superior toughness—better resistance to cracking and gross fracture
• Enhanced thermal fatigue resistance—longer life before heat checking appears
• Cleaner microstructure—fewer inclusions that can initiate cracks
• Longer service life—8407 achieves 150,000-200,000 shots compared to H13’s 80,000-100,000 shots

Where manufacturers apply premium grades:

High-volume automotive production. When you need maximum tool life for high-volume runs, premium grades justify their higher cost. The improved toughness and thermal fatigue resistance translate directly into fewer mould replacements and less downtime.

Complex or demanding geometries. Thin-wall mobile device housings and parts with intricate details place higher stress on the mould. Premium grades handle these conditions better than standard H13.

High-pressure die casting applications. 8407 offers excellent resistance to heat, wear, and corrosion, making it suitable for high-pressure die casting environments.

Complex moulds requiring long service life. 8407 is often chosen for complex die casting moulds that require precise dimensions and extended operational life.

Haichen’s premium grade solutions. Haichen works with mould makers who use premium grades like 8407 and DIEVAR for customers with the most demanding production requirements. We help buyers evaluate the total cost of ownership—balancing higher upfront material costs against longer tool life and reduced downtime. Haichen’s die casting machines are designed to work with moulds made from all premium grades, ensuring compatibility and optimal performance.

How Material Selection Affects Mould Performance

Thermal Fatigue Resistance

Thermal fatigue—heat checking—is the dominant failure mechanism in die casting moulds. The repeated heating and cooling of each cycle creates thermal stress that eventually causes surface cracking. Materials with higher thermal fatigue resistance, like premium H13 grades, DAC55, and DIEVAR, last longer before heat checking appears.

Haichen’s guidance: If your mould shows heat checking after fewer than 50,000 shots, consider upgrading to a premium-grade material. Haichen’s technical team can analyse your production data and recommend the optimal material upgrade.

Erosion and Corrosion Resistance

Molten metal flow erodes mould surfaces over time, particularly at gates and other high-velocity areas. Aluminum is more chemically aggressive toward tool steel than zinc, so aluminium die casting moulds need better corrosion resistance.

Haichen’s guidance: For aluminum die casting, prioritise materials with good corrosion resistance like premium H13 or 8407. For zinc, standard H13 or SKD61 often suffices. Haichen’s engineers provide material recommendations based on your specific alloy.

Toughness vs. Hardness Trade-off

Harder steels resist wear better but can be more brittle. Tougher steels resist cracking but may wear faster. The right balance depends on your specific application—high-pressure, high-temperature applications need both.

Haichen’s guidance: Work with Haichen’s technical team to select the material that balances hardness and toughness for your specific alloy and production conditions. Our experience across multiple industries helps buyers make the right trade-off.

Heat Treatment and Its Impact on Material Performance

Why does heat treatment matter? Heat treatment transforms the steel’s microstructure, determining its hardness, toughness, and resistance to thermal fatigue. Improper heat treatment creates residual stresses and increases brittleness, becoming a primary cause of early failure.

Common heat treatment processes:

• Annealing. Softens the steel for machining before hardening.
• Quenching and tempering. Hardens the steel to achieve the required mechanical properties.
• Surface treatments. Nitriding or other surface hardening processes improve wear resistance.

What heat treatment achieves:

• Proper heat treatment extends service life by 100-200% in some applications
• Premium grades like DAC55 offer improved hardenability and can be used at higher hardness levels (50-53 HRC)

Haichen’s heat treatment expertise. Haichen helps buyers verify their mould supplier’s heat treatment capabilities and quality control processes. We understand that the best mould material fails without proper heat treatment, so we guide buyers through the critical steps of material selection, heat treatment verification, and ongoing maintenance.

Common Failure Modes and How Material Choice Affects Them

Thermal fatigue cracking (heat checking). This is the most common failure mode in die casting dies. Repeated thermal cycling causes surface cracks that grow deeper with each cycle. Premium materials with better thermal fatigue resistance delay the onset of heat checking.

Erosion. Molten metal flow erodes mould surfaces, particularly at gates and other high-velocity areas. Materials with higher hardness and wear resistance resist erosion better.

Corrosion. Chemical reactions between molten metal and tool steel degrade mould surfaces. Materials with better corrosion resistance—some premium grades—last longer in aggressive environments.

Soldering. Molten metal adheres to the mould surface, causing damage when the part ejects. Proper surface treatments and material selection reduce soldering.

Gross fracture. Catastrophic cracking from mechanical overloading or severe thermal stress. Higher toughness materials like DAC55 and DIEVAR resist gross fracture better.

Haichen’s failure analysis support. Haichen provides failure analysis support to help buyers identify the root cause of mould failures. By understanding which failure mode limits your mould life, Haichen’s technical team helps you select the right material for your specific application.

Questions you may have

• “What material do you recommend for my alloy and production volume?” – The answer should reflect your specific application, not just what they stock.
• “What is the expected service life for this material under my conditions?” – Get a clear number based on your alloy and cycle count.
• “What heat treatment process do you use?” – Proper heat treatment is as important as material selection.
• “Do you offer premium-grade alternatives like DAC55 or DIEVAR?” – These may deliver better value for high-volume production.
• “What quality control measures do you use for material certification?” – Verify that you receive the grade you pay for.
• “Can you provide case studies from similar applications?” – Proven results matter more than promises.
• “What is your lead time for material procurement and mould manufacturing?” – Premium grades sometimes have longer lead times.

Need help selecting the right mould material for your die casting operation? Contact Haichen Machinery. We will analyse your alloy, production targets, and budget to recommend the optimal mould material for your specific needs.