The Impact of Thermal Conductivity Mold Material in the Injection Molding Process

International Journal of Mechanical Engineering

© 2025 by SSRG - IJME Journal

Volume 12 Issue 5

Year of Publication : 2025

Authors : Jagadeesan. S, Annamalai. K

10.14445/23488360/IJME-V12I5P104

How to Cite?

Jagadeesan. S, Annamalai. K, "The Impact of Thermal Conductivity Mold Material in the Injection Molding Process," SSRG International Journal of Mechanical Engineering, vol. 12,  no. 5, pp. 27-40, 2025. Crossref, https://doi.org/10.14445/23488360/IJME-V12I5P104

Abstract:

Removing heat from an injection mold, part solidification, and factors that control and eliminate shrinkage and warpage are important in the injection molding process. As the injection molding process progresses, the time taken to remove the heat energy is equivalent to the amount of heat removed from the polymer melt by cooling. This study investigates the strategies employing Beryllium copper material application in thermal conductivity to resolve the issues on mold cooling and give a better effect of change in temperature and change in thermal conductivity since the mold material is a major factor in temperature control. Beryllium copper has two times the thermal conductivity value compared to steel and about four times the stainless-steel material. Minimizing cooling time plays a crucial role in reducing the cycle time during the injection molding process. Based on the material change for the core pin and the subsequent trial taken, the observations are a reduction of filling and 100% balancing of the fill pattern without any short filling. Uniform filling and packing occurred with a maximum injection pressure of 65.61 MPa, reduced from 80 MPa to fill the part. Factors such as melt viscosity, melt temperature, mold temperature, and packing parameters significantly influence the final pressure needs. The author finds that Beryllium copper reduces molding cycle time from 32 seconds to 28 seconds by cooling time reduction, provides uniform cooling to produce defect-free components, and increases productivity by 12.50% in real-time production. Hence, Beryllium copper plays a prominent role in injection molding cooling time determination in the area of cycle time reduction to improve productivity in mass-production industries.

Keywords:

Beryllium copper, Cooling time, Core pin, Ejection temperature, Productivity.

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