Die Temperature Control in Die Casting: The Core of High-Quality and Reliable Production

In the increasingly competitive die-casting industry, companies consistently pursue higher product qualification rates, more stable production efficiency, and longer mold lifespans. The key to achieving these goals often lies in a frequently overlooked yet crucial aspect: die temperature control. Precision mold temperature management is not merely an auxiliary process but an indispensable core technology in modern aluminum alloy die-casting production.

Why is Die Temperature Control Essential?

During the die-casting process, high-temperature molten metal fills the mold cavity at extreme speeds, introducing immense heat. If this heat is not managed effectively and evenly, a cascade of problems can arise. For the product, an uneven mold temperature can lead to defects such as flow lines, cold shuts, and shrinkage porosity, severely impacting internal integrity and surface quality. For the mold itself, localized overheating can cause soldering, sticking, and even lead to temper softening and accelerated thermal fatigue of the mold steel, drastically reducing its service life. Therefore, operating without effective temperature control is akin to walking a tightrope over the high costs of molds and production uncertainties.

What Constitutes Scientific Die Temperature Control?

Die temperature control in die-casting extends far beyond simple "cooling." It is a comprehensive process that involves the precise regulation and maintenance of the mold's operating temperature through active heating and cooling methods. The goal is to keep the mold within a predetermined, uniform, and stable optimal temperature range throughout the entire production cycle. Before production begins, the mold must be preheated to its ideal operating temperature using methods like oil, water, or electric heating to avoid initial scrap parts from a cold start. During production, the temperature control system performs two core tasks: firstly, it rapidly removes the substantial heat released by the solidifying metal through cooling channels, preventing mold overheating and shortening cycle times to boost efficiency; secondly, it compensates for heat loss in areas prone to cooling, such as thin walls or regions far from the gate, ensuring thermal balance across the mold. Only in this way can the filling and solidification behavior of the molten metal be optimized, ultimately producing high-quality, consistent castings.

How to Systematically Design Die Temperature Control?

A successful temperature control system design begins with precise heat calculation and concludes with simulation verification and optimization—a rigorous engineering process.

First, the total heat input per cycle from the molten metal must be accurately calculated. Taking aluminum alloy as an example, for every 1kg of alloy solidifying as it cools from 630°C to 360°C, the heat released is as high as 563 kJ (calculation includes specific heat capacity and latent heat). This heat must be effectively removed before the next casting cycle; otherwise, the mold temperature will continuously rise, disrupting production stability.

Secondly, it is necessary to reasonably estimate the die-casting cycle time and clarify the distribution of heat removal. Typically, cooling water bears the responsibility of removing approximately 50% to 80% of this heat, with the exact proportion depending on the spray type—around 65% for water-based sprays, 70% for oil-based, and highly efficient micro-spraying demands the cooling system remove up to 80% of the heat. This is precisely why micro-spray technology has gained significant favor in recent years; it trades higher demands on cooling system design for gains in both production cycle time and mold life.

Subsequently, the core cooling system design phase begins. The first step is "Zoning," which involves identifying high-temperature zones (e.g., near the gate, thick sections), medium-temperature zones, and low-temperature zones based on the casting geometry, and matching them with appropriate control methods. This might mean intensified cooling in hot zones and potentially supplemental heating in cold zones, aiming to achieve relatively similar solidification rates throughout the casting. The second step is precisely identifying locations for cooling channels while ensuring a safe distance is maintained between the channels and the mold cavity wall. The third step involves determining the diameter, length, and layout of the cooling channels. Channel length affects heat transfer efficiency, with shorter channels benefiting from the "Entry Effect," resulting in a higher average heat transfer coefficient. Finally, the inlet and outlet positions must be rationally designed to form an efficient and orderly heat exchange.

Upon completion of the design, verification using professional temperature field simulation software is an indispensable step. Simulation allows for intuitive analysis of the temperature distribution across the mold, identifying hot spots or cold spots in the design. Based on these results, adjustments can be made, such as adding inserts, thermal barriers, or modifying cooling channels, thereby optimizing the design before committing to physical production.

In summary, die temperature control technology in die-casting is a systems engineering discipline integrating thermodynamics, fluid mechanics, and materials science. It is no longer an optional extra but a necessary path for die-casting companies striving for high-quality, high-efficiency, and low-cost manufacturing. From precise heat calculation to scientific cooling design, and finally to simulation verification, building a stable and reliable mold temperature control system is a strategic investment that safeguards product competitiveness and enhances corporate economic效益.

EDT Die Casting Technology – Your Trusted Die Casting Partner

If you are looking for a reliable partner for custom precision parts and die-cast component manufacturing, EDT Die Casting Technology (Suzhou) Co., Ltd. is your ideal choice.

We specialize in zinc and aluminum alloy die casting, leveraging advanced European die-casting technology and management systems. Our facility is equipped with fully automated melting, die casting, machining, and inspection equipment, ensuring every product meets high-quality standards.

Whether you require complex structural components, high-precision housings, or parts with special material performance requirements, we can provide a one-stop solution from mold development to final product delivery through scientific process design and rigorous production control.

Choosing EDT means choosing Quality, Efficiency, and Trust!