Articles

Core elements are fundamental in the die-casting process for creating cavities or lightweight features inside metal castings.

	Their strength, porosity, and ability to withstand high temperatures without compromising the final product quality are essential requirements. Traditionally, cores are made using organic binders, which unfortunately generate harmful emissions, including fumes and gases, during the casting of molten metal.

Advantages of Inorganic Binders

Inorganic binders offer several advantages over organic binders. Composed of 98-99% non-organic substances, these binders do not produce toxic fumes, significantly reducing harmful emissions in the workplace environment. However, one of the main issues associated with inorganic binders is their instability in high humidity environments, which can reduce the lifespan of the cores and cause gas inclusions in the casting.

Development of a Bicomponent Inorganic System

To address this challenge, Jodovit has developed a bicomponent inorganic binder system, designed to reduce environmental moisture absorption and improve core performance without compromising the finished product quality. This innovative system uses a combination of silicates, phosphates, and borates, which help maintain the stability of the core in high humidity conditions, reducing casting defects such as gas inclusion formation.

Production Process of Cores with Inorganic Binders

The production process for cores using inorganic binders involves mixing sand with a liquid binder and a powder promoter. The sand is compacted into a heated core box, and hardening occurs through a physical dehydration process or, alternatively, by using microwaves to accelerate the hardening process. Thanks to the reduced moisture absorption, the produced cores are more durable and resilient, improving the quality of the final casting.

Results and Comparison with Other Binder Systems

Various laboratory tests have shown that the bicomponent inorganic binder system, such as the INEX SYSTEM, provides superior performance compared to traditional binders. Tests highlighted greater uniaxial compressive strength and moisture reduction compared to competing binders, without compromising the quality of the finished piece. Additionally, the adoption of second-generation promoters, completely free of organic substances, has further improved the stability and sterility properties of the cores.

Environmental Benefits and Sustainability

The adoption of inorganic binders for core production not only improves technical performance but also represents an important step towards a more sustainable production. By eliminating toxic fumes and reducing moisture absorption, this system contributes to a safer work environment and a lower incidence of defects in castings. In an industrial context increasingly focused on sustainability, introducing innovative solutions such as bicomponent inorganic binders is essential to ensure more environmentally friendly and efficient manufacturing processes.

Conclusions

The evolution of inorganic binders for core production represents a significant breakthrough in the light metal foundry industry. With the innovation of bicomponent systems and the improvement of moisture resistance properties, the industry can not only improve casting quality but also significantly reduce environmental impact. Investing in these advanced technologies means embracing a greener, more efficient, and safer future for all.

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